Freescale MC9S12P128J0MFT S12 microcontroller Datasheet

MC9S12P128
Reference Manual
Covers also MC9S12P-Family
MC9S12P96
MC9S12P64
MC9S12P32
S12
Microcontrollers
MC9S12P128RMV1
Rev. 1.13
23 April 2010
freescale.com
To provide the most up-to-date information, the revision of our documents on the World Wide Web will be
the most current. Your printed copy may be an earlier revision. To verify you have the latest information
available, refer to:
http://freescale.com/
A full list of family members and options is included in the appendices.
The following revision history table summarizes changes contained in this document.
This document contains information for all constituent modules, with the exception of the CPU. For CPU
information please refer to CPU12-1 in the CPU12 & CPU12X Reference Manual.
Revision History
Date
Revision
Level
April 2008
1.07
PRELIMINARY
July 2008
1.08
Minor Corrections
Added typ. IDD values
December 2008
1.09
Completed Electricals
Minor Corrections
March 2009
1.10
Final Electricals
June 2009
1.11
Corrected section 1.11.3.4 Memory
Corrected 1.7.3.16 - 1.7.3.19 SPI pin description
Removed reference to MMCCTL1 register from Table 13-5
Removed item 4b from Table A-6 and A-7
Changed Version ID in Table 1-5 from $FF to $00
October 2009
1.12
Added Register Summary Appendix D
Updated FTMRC Blockguide . See Revision History Chapter 13
Updated CPMU Blockguide . See Revision History Chapter 7
April 2010
1.13
Updated S12PMMCV1 Blockguide. See Revision History Chapter 3
Updated S12CPMU Blockguide. See Revision History Chapter 7
Description
Chapter 1
Device Overview MC9S12P-Family . . . . . . . . . . . . . . . . . . . . . . 17
Chapter 2
Port Integration Module (S12PPIMV1) . . . . . . . . . . . . . . . . . . . 49
Chapter 3
Memory Map Control (S12PMMCV1). . . . . . . . . . . . . . . . . . . . 107
Chapter 4
Interrupt Module (S12SINTV1). . . . . . . . . . . . . . . . . . . . . . . . . 123
Chapter 5
Background Debug Module (S12SBDMV1) . . . . . . . . . . . . . . 131
Chapter 6
S12S Debug Module (S12SDBGV2) . . . . . . . . . . . . . . . . . . . . 155
Chapter 7
S12 Clock, Reset and Power Management Unit (S12CPMU) 197
Chapter 8
251
Freescale’s Scalable Controller Area Network (S12MSCANV3).
Chapter 9
Analog-to-Digital Converter (ADC12B10C) . . . . . . . . . . . . . . 305
Chapter 10
Pulse-Width Modulator (PWM8B6CV1) Block Description . . 329
Chapter 11
Serial Communication Interface (S12SCIV5) . . . . . . . . . . . . . 363
Chapter 12
Serial Peripheral Interface (S12SPIV5) . . . . . . . . . . . . . . . . . . 399
Chapter 13
128 KByte Flash Module (S12FTMRC128K1V1). . . . . . . . . . . 425
Chapter 14
Timer Module (TIM16B8CV2) Block Description . . . . . . . . . . 473
Appendix A Electrical Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 501
Appendix B Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 533
Appendix C Package Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 535
Appendix D Detailed Register Address Map. . . . . . . . . . . . . . . . . . . . . . . . 545
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Chapter 1Device Overview MC9S12P-Family
1.1
1.2
1.3
1.4
1.5
1.6
1.7
1.8
1.9
1.10
1.11
1.12
1.13
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
1.2.1 MC9S12P Family Comparison . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
1.2.2 Chip-Level Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Module Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
1.3.1 S12 16-Bit Central Processor Unit (CPU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
1.3.2 On-Chip Flash with ECC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
1.3.3 On-Chip SRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
1.3.4 Main External Oscillator (XOSC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
1.3.5 Internal RC Oscillator (IRC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
1.3.6 Internal Phase-Locked Loop (IPLL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
1.3.7 System Integrity Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
1.3.8 Timer (TIM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
1.3.9 Pulse Width Modulation Module (PWM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
1.3.10 Controller Area Network Module (MSCAN) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
1.3.11 Serial Communication Interface Module (SCI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
1.3.12 Serial Peripheral Interface Module (SPI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
1.3.13 Analog-to-Digital Converter Module (ATD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
1.3.14 On-Chip Voltage Regulator (VREG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
1.3.15 Background Debug (BDM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
1.3.16 Debugger (DBG) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Device Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
Part ID Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
1.7.1 Device Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
1.7.2 Pin Assignment Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
1.7.3 Detailed Signal Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
1.7.4 Power Supply Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
System Clock Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
1.9.1 Chip Configuration Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
1.9.2 Low Power Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Resets and Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
1.11.1 Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
1.11.2 Interrupt Vectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
1.11.3 Effects of Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
COP Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
ATD External Trigger Input Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
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1.14 S12CPMU Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Chapter 2
Port Integration Module (S12PPIMV1)
2.1
2.2
2.3
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
2.1.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
2.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
2.3.1 Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52
2.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
2.3.3 Port A Data Register (PORTA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
2.3.4 Port B Data Register (PORTB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63
2.3.5 Port A Data Direction Register (DDRA) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
2.3.6 Port B Data Direction Register (DDRB) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
2.3.7 PIM Reserved Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
2.3.8 Port E Data Register (PORTE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
2.3.9 Port E Data Direction Register (DDRE) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
2.3.10 Ports A, B, E, BKGD pin Pull-up Control Register (PUCR) . . . . . . . . . . . . . . . . . . . . . 67
2.3.11 Ports A, B, E Reduced Drive Register (RDRIV) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
2.3.12 ECLK Control Register (ECLKCTL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
2.3.13 PIM Reserved Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
2.3.14 IRQ Control Register (IRQCR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
2.3.15 PIM Reserved Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
2.3.16 Port T Data Register (PTT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
2.3.17 Port T Input Register (PTIT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
2.3.18 Port T Data Direction Register (DDRT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73
2.3.19 Port T Reduced Drive Register (RDRT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
2.3.20 Port T Pull Device Enable Register (PERT) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
2.3.21 Port T Polarity Select Register (PPST) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
2.3.22 PIM Reserved Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
2.3.23 Port T Routing Register (PTTRR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76
2.3.24 Port S Data Register (PTS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
2.3.25 Port S Input Register (PTIS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 77
2.3.26 Port S Data Direction Register (DDRS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78
2.3.27 Port S Reduced Drive Register (RDRS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
2.3.28 Port S Pull Device Enable Register (PERS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79
2.3.29 Port S Polarity Select Register (PPSS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
2.3.30 Port S Wired-Or Mode Register (WOMS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
2.3.31 PIM Reserved Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
2.3.32 Port M Data Register (PTM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
2.3.33 Port M Input Register (PTIM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 82
2.3.34 Port M Data Direction Register (DDRM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
2.3.35 Port M Reduced Drive Register (RDRM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
2.3.36 Port M Pull Device Enable Register (PERM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
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2.3.37 Port M Polarity Select Register (PPSM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
2.3.38 Port M Wired-Or Mode Register (WOMM) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
2.3.39 PIM Reserved Register . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
2.3.40 Port P Data Register (PTP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
2.3.41 Port P Input Register (PTIP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
2.3.42 Port P Data Direction Register (DDRP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
2.3.43 Port P Reduced Drive Register (RDRP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 89
2.3.44 Port P Pull Device Enable Register (PERP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
2.3.45 Port P Polarity Select Register (PPSP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 90
2.3.46 Port P Interrupt Enable Register (PIEP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
2.3.47 Port P Interrupt Flag Register (PIFP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
2.3.48 PIM Reserved Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
2.3.49 Port J Data Register (PTJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
2.3.50 Port J Input Register (PTIJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
2.3.51 Port J Data Direction Register (DDRJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
2.3.52 Port J Reduced Drive Register (RDRJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
2.3.53 Port J Pull Device Enable Register (PERJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 94
2.3.54 Port J Polarity Select Register (PPSJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
2.3.55 Port J Interrupt Enable Register (PIEJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 95
2.3.56 Port J Interrupt Flag Register (PIFJ) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
2.3.57 Port AD Data Register (PT0AD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
2.3.58 Port AD Data Register (PT1AD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
2.3.59 Port AD Data Direction Register (DDR0AD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
2.3.60 Port AD Data Direction Register (DDR1AD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
2.3.61 Port AD Reduced Drive Register (RDR0AD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98
2.3.62 Port AD Reduced Drive Register (RDR1AD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
2.3.63 Port AD Pull Up Enable Register (PER0AD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
2.3.64 Port AD Pull Up Enable Register (PER1AD) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
2.3.65 PIM Reserved Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
2.4.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
2.4.2 Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
2.4.3 Pins and Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 103
2.4.4 Pin interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105
Initialization Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
2.5.1 Port Data and Data Direction Register writes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Chapter 3
Memory Map Control (S12PMMCV1)
3.1
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
3.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
3.1.2 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
3.1.3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
3.1.4 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
3.1.5 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 108
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3.2
3.3
3.4
3.5
3.6
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Memory Map and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
3.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
3.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
3.4.1 MCU Operating Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 113
3.4.2 Memory Map Scheme . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114
Implemented Memory in the System Memory Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . 117
3.5.1 Chip Bus Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
3.5.2 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
3.6.1 CALL and RTC Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Chapter 4
Interrupt Module (S12SINTV1)
4.1
4.2
4.3
4.4
4.5
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
4.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
4.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
4.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
4.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
4.3.1 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
4.4.1 S12S Exception Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
4.4.2 Interrupt Prioritization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126
4.4.3 Reset Exception Requests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
4.4.4 Exception Priority . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
4.5.1 Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
4.5.2 Interrupt Nesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
4.5.3 Wake Up from Stop or Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Chapter 5
Background Debug Module (S12SBDMV1)
5.1
5.2
5.3
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
5.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
5.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 132
5.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 133
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
5.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
5.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
5.3.3 Family ID Assignment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
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5.4
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
5.4.1 Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
5.4.2 Enabling and Activating BDM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
5.4.3 BDM Hardware Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
5.4.4 Standard BDM Firmware Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
5.4.5 BDM Command Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
5.4.6 BDM Serial Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 143
5.4.7 Serial Interface Hardware Handshake Protocol . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
5.4.8 Hardware Handshake Abort Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
5.4.9 SYNC — Request Timed Reference Pulse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
5.4.10 Instruction Tracing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151
5.4.11 Serial Communication Time Out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 152
Chapter 6
S12S Debug Module (S12SDBGV2)
6.1
6.2
6.3
6.4
6.5
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
6.1.1 Glossary Of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
6.1.2 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
6.1.3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 156
6.1.4 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
6.1.5 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 157
Memory Map and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
6.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
6.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 159
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
6.4.1 S12SDBG Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174
6.4.2 Comparator Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
6.4.3 Match Modes (Forced or Tagged) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179
6.4.4 State Sequence Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 180
6.4.5 Trace Buffer Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181
6.4.6 Tagging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
6.4.7 Breakpoints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 187
Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
6.5.1 State Machine scenarios . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 189
6.5.2 Scenario 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
6.5.3 Scenario 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 190
6.5.4 Scenario 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
6.5.5 Scenario 4 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
6.5.6 Scenario 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
6.5.7 Scenario 6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
6.5.8 Scenario 7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
6.5.9 Scenario 8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
6.5.10 Scenario 9 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
6.5.11 Scenario 10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194
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Chapter 7
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.1
7.2
7.3
7.4
7.5
7.6
7.7
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
7.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 197
7.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199
7.1.3 S12CPMU Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 201
Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
7.2.1 RESET . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
7.2.2 EXTAL and XTAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202
7.2.3 TEMPSENSE — temperature sensor output voltage . . . . . . . . . . . . . . . . . . . . . . . . . . 203
7.2.4 VDDR — Regulator Power Input Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
7.2.5 VDDA, VSSA — Regulator Reference Supply Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
7.2.6 VSS, VSSPLL— Ground Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
7.2.7 VDDX, VSSX— Pad Supply Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
7.2.8 API_EXTCLK — API external clock output pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
Memory Map and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
7.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
7.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
7.4.1 Phase Locked Loop with Internal Filter (PLL) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
7.4.2 Startup from Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
7.4.3 Stop Mode using PLLCLK as Bus Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
7.4.4 Full Stop Mode using Oscillator Clock as Bus Clock . . . . . . . . . . . . . . . . . . . . . . . . . . 240
7.4.5 External Oscillator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
7.4.6 System Clock Configurations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 244
Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
7.5.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
7.5.2 Description of Reset Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 246
7.5.3 Power-On Reset (POR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
7.5.4 Low-Voltage Reset (LVR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
7.6.1 Description of Interrupt Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 249
Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
Chapter 8
Freescale’s Scalable Controller Area Network (S12MSCANV3)
8.1
8.2
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 251
8.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
8.1.2 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 252
8.1.3 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
8.1.4 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
8.2.1 RXCAN — CAN Receiver Input Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
8.2.2 TXCAN — CAN Transmitter Output Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
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8.3
8.4
8.5
8.2.3 CAN System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
8.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 254
8.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
8.3.3 Programmer’s Model of Message Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285
8.4.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 285
8.4.2 Message Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 286
8.4.3 Identifier Acceptance Filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
8.4.4 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
8.4.5 Low-Power Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
8.4.6 Reset Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
8.4.7 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 301
Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
8.5.1 MSCAN initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
8.5.2 Bus-Off Recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 303
Chapter 9
Analog-to-Digital Converter (ADC12B10C)
9.1
9.2
9.3
9.4
9.5
9.6
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
9.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 305
9.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
9.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
9.2.1 Detailed Signal Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
9.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 308
9.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 324
9.4.1 Analog Sub-Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
9.4.2 Digital Sub-Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 325
Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 326
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
Chapter 10
Pulse-Width Modulator (PWM8B6CV1) Block Description
10.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
10.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
10.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
10.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
10.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
10.2.1 PWM5 — Pulse Width Modulator Channel 5 Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
10.2.2 PWM4 — Pulse Width Modulator Channel 4 Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
10.2.3 PWM3 — Pulse Width Modulator Channel 3 Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
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10.4
10.5
10.6
10.2.4 PWM2 — Pulse Width Modulator Channel 2 Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
10.2.5 PWM1 — Pulse Width Modulator Channel 1 Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
10.2.6 PWM0 — Pulse Width Modulator Channel 0 Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
10.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
10.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352
10.4.1 PWM Clock Select . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352
10.4.2 PWM Channel Timers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 362
Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 362
Chapter 11
Serial Communication Interface (S12SCIV5)
11.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
11.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
11.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
11.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
11.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
11.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
11.2.1 TXD — Transmit Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
11.2.2 RXD — Receive Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
11.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 365
11.3.1 Module Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366
11.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 366
11.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 376
11.4.1 Infrared Interface Submodule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 377
11.4.2 LIN Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
11.4.3 Data Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
11.4.4 Baud Rate Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 380
11.4.5 Transmitter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 381
11.4.6 Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 386
11.4.7 Single-Wire Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394
11.4.8 Loop Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395
11.5 Initialization/Application Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395
11.5.1 Reset Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395
11.5.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 395
11.5.3 Interrupt Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 396
11.5.4 Recovery from Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398
11.5.5 Recovery from Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398
Chapter 12
Serial Peripheral Interface (S12SPIV5)
12.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399
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12.1.1 Glossary of Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399
12.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399
12.1.3 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 399
12.1.4 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 400
12.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401
12.2.1 MOSI — Master Out/Slave In Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401
12.2.2 MISO — Master In/Slave Out Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 401
12.2.3 SS — Slave Select Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402
12.2.4 SCK — Serial Clock Pin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402
12.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402
12.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 402
12.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
12.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 411
12.4.1 Master Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 412
12.4.2 Slave Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
12.4.3 Transmission Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 414
12.4.4 SPI Baud Rate Generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
12.4.5 Special Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 420
12.4.6 Error Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 421
12.4.7 Low Power Mode Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
Chapter 13
128 KByte Flash Module (S12FTMRC128K1V1)
13.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 425
13.1.1 Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 426
13.1.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 427
13.1.3 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 427
13.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 428
13.3 Memory Map and Registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
13.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 429
13.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 432
13.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450
13.4.1 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450
13.4.2 IFR Version ID Word . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450
13.4.3 Flash Command Operations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 450
13.4.4 Allowed Simultaneous P-Flash and D-Flash Operations . . . . . . . . . . . . . . . . . . . . . . . . 455
13.4.5 Flash Command Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 455
13.4.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 469
13.4.7 Wait Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470
13.4.8 Stop Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470
13.5 Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470
13.5.1 Unsecuring the MCU using Backdoor Key Access . . . . . . . . . . . . . . . . . . . . . . . . . . . . 470
13.5.2 Unsecuring the MCU in Special Single Chip Mode using BDM . . . . . . . . . . . . . . . . . 471
13.5.3 Mode and Security Effects on Flash Command Availability . . . . . . . . . . . . . . . . . . . . . 472
13.6 Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 472
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Chapter 14
Timer Module (TIM16B8CV2) Block Description
14.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 473
14.1.1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 474
14.1.2 Modes of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 474
14.1.3 Block Diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 475
14.2 External Signal Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 477
14.2.1 IOC7 — Input Capture and Output Compare Channel 7 Pin . . . . . . . . . . . . . . . . . . . . 477
14.2.2 IOC6 — Input Capture and Output Compare Channel 6 Pin . . . . . . . . . . . . . . . . . . . . 477
14.2.3 IOC5 — Input Capture and Output Compare Channel 5 Pin . . . . . . . . . . . . . . . . . . . . 477
14.2.4 IOC4 — Input Capture and Output Compare Channel 4 Pin . . . . . . . . . . . . . . . . . . . . 477
14.2.5 IOC3 — Input Capture and Output Compare Channel 3 Pin . . . . . . . . . . . . . . . . . . . . 477
14.2.6 IOC2 — Input Capture and Output Compare Channel 2 Pin . . . . . . . . . . . . . . . . . . . . 477
14.2.7 IOC1 — Input Capture and Output Compare Channel 1 Pin . . . . . . . . . . . . . . . . . . . . 478
14.2.8 IOC0 — Input Capture and Output Compare Channel 0 Pin . . . . . . . . . . . . . . . . . . . . 478
14.3 Memory Map and Register Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 478
14.3.1 Module Memory Map . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 478
14.3.2 Register Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 478
14.4 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 495
14.4.1 Prescaler . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 496
14.4.2 Input Capture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497
14.4.3 Output Compare . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 497
14.4.4 Pulse Accumulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498
14.4.5 Event Counter Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498
14.4.6 Gated Time Accumulation Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 498
14.5 Resets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
14.6 Interrupts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
14.6.1 Channel [7:0] Interrupt (C[7:0]F) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
14.6.2 Pulse Accumulator Input Interrupt (PAOVI) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
14.6.3 Pulse Accumulator Overflow Interrupt (PAOVF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 499
14.6.4 Timer Overflow Interrupt (TOF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 500
Appendix A
Electrical Characteristics
A.1 General
A.1.1
A.1.2
A.1.3
A.1.4
A.1.5
A.1.6
A.1.7
A.1.8
A.1.9
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 501
Parameter Classification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 501
Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 501
Pins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 502
Current Injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 502
Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 502
ESD Protection and Latch-up Immunity. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503
Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 504
Power Dissipation and Thermal Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 505
I/O Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 508
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A.2
A.3
A.4
A.5
A.6
A.7
A.8
A.9
A.10
A.11
A.1.10 Supply Currents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 510
ATD Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 512
A.2.1 ATD Operating Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 512
A.2.2 Factors Influencing Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 513
A.2.3 ATD Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 514
NVM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 518
A.3.1 Timing Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 518
A.3.2 NVM Reliability Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 522
Phase Locked Loop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 523
A.4.1 Jitter Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 523
A.4.2 Electrical Characteristics for the PLL. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525
Electrical Characteristics for the IRC1M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 525
Electrical Characteristics for the Oscillator (OSCLCP) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 526
Reset Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 526
Electrical Specification for Voltage Regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 527
Chip Power-up and Voltage Drops . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 527
MSCAN. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 529
SPI Timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 529
A.11.1 Master Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 529
A.11.2 Slave Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 531
Appendix B
Ordering Information
Appendix C
Package Information
C.1 80 QFP Package Mechanical Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 536
C.2 48 QFN Package Mechanical Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 539
C.3 64 LQFP Package Mechanical Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 542
Appendix D
Detailed Register Address Map
D.1 Detailed Register Map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 545
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Chapter 1 Device Overview MC9S12P-Family
1.1
Introduction
The MC9S12P family is an optimized, automotive, 16-bit microcontroller product line focused on lowcost, high-performance, and low pin-count. This family is intended to bridge between high-end 8-bit
microcontrollers and high-performance 16-bit microcontrollers, such as the MC9S12XS family. The
MC9S12P family is targeted at generic automotive applications requiring CAN or LIN/J2602
communication. Typical examples of these applications include body controllers, occupant detection, door
modules, seat controllers, RKE receivers, smart actuators, lighting modules, and smart junction boxes.
The MC9S12P family uses many of the same features found on the MC9S12XS family, including error
correction code (ECC) on flash memory, a separate data-flash module for diagnostic or data storage, a fast
analog-to-digital converter (ATD) and a frequency modulated phase locked loop (IPLL) that improves the
EMC performance.
The MC9S12P family deliver all the advantages and efficiencies of a 16-bit MCU while retaining the low
cost, power consumption, EMC, and code-size efficiency advantages currently enjoyed by users of
Freescale’s existing 8-bit and 16-bit MCU families. Like the MC9S12XS family, the MC9S12P family run
16-bit wide accesses without wait states for all peripherals and memories. The MC9S12P family is
available in 80-pin QFP, 64-pin LQFP, and 48-pin QFN package options and aims to maximize pin
compatibility with the MC9S12XS family. In addition to the I/O ports available in each module, further
I/O ports are available with interrupt capability allowing wake-up from stop or wait modes.
1.2
Features
This section describes the key features of the MC9S12P family.
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Device Overview MC9S12P-Family
1.2.1
MC9S12P Family Comparison
Table 1 provides a summary of different members of the MC9S12P family and their proposed features.
This information is intended to provide an understanding of the range of functionality offered by this
microcontroller family.
Table 1. MC9S12P Family
Feature
MC9S12P32
MC9S12P64
CPU
MC9S12P96
MC9S12P128
96 Kbytes
128 Kbytes
CPU12-V1
Flash memory (ECC)
32 Kbytes
64 Kbytes
Data flash (ECC)
RAM
4 Kbytes
2 Kbytes
4 Kbytes
6 Kbytes
MSCAN
1
SCI
1
SPI
1
Timer
8 ch x 16-bit
PWM
6 ch x 8-bit
ADC
10 ch x 12-bit
Frequency modulated PLL
Yes
External oscillator
(4 – 16 MHz Pierce with
loop control)
Yes
Internal 1 MHz RC
oscillator
Yes
Supply voltage
3.15 V – 5.5 V
Static(1) – 32 MHz
Execution speed
Package
80 QFP, 64 LQFP, 48 QFN
1. P or D Flash erasing or programming requires a minimum bus frequency of 1MHz
1.2.2
Chip-Level Features
On-chip modules available within the family include the following features:
• S12 CPU core
• Up to 128 Kbyte on-chip flash with ECC
• 4 Kbyte data flash with ECC
• Up to 6 Kbyte on-chip SRAM
• Phase locked loop (IPLL) frequency multiplier with internal filter
• 4–16 MHz amplitude controlled Pierce oscillator
• 1 MHz internal RC oscillator
• Timer module (TIM) supporting input/output channels that provide a range of 16-bit input capture,
output compare, counter, and pulse accumulator functions
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Device Overview MC9S12P-Family
•
•
•
•
•
•
•
1.3
Pulse width modulation (PWM) module with 6 x 8-bit channels
10-channel, 12-bit resolution successive approximation analog-to-digital converter (ATD)
One serial peripheral interface (SPI) module
One serial communication interface (SCI) module supporting LIN communications
One multi-scalable controller area network (MSCAN) module (supporting CAN protocol 2.0A/B)
On-chip voltage regulator (VREG) for regulation of input supply and all internal voltages
Autonomous periodic interrupt (API)
Module Features
The following sections provide more details of the modules implemented on the MC9S12P family.
1.3.1
S12 16-Bit Central Processor Unit (CPU)
S12 CPU is a high-speed 16-bit processing unit:
• Full 16-bit data paths supports efficient arithmetic operation and high-speed math execution
• Includes many single-byte instructions. This allows much more efficient use of ROM space.
• Extensive set of indexed addressing capabilities, including:
— Using the stack pointer as an indexing register in all indexed operations
— Using the program counter as an indexing register in all but auto increment/decrement mode
— Accumulator offsets using A, B, or D accumulators
— Automatic index predecrement, preincrement, postdecrement, and postincrement (by –8 to +8)
1.3.2
On-Chip Flash with ECC
On-chip flash memory on the MC9S12P features the following:
• Up to 128 Kbyte of program flash memory
— 32 data bits plus 7 syndrome ECC (error correction code) bits allow single bit error correction
and double fault detection
— Erase sector size 512 bytes
— Automated program and erase algorithm
— User margin level setting for reads
— Protection scheme to prevent accidental program or erase
• 4 Kbyte data flash space
— 16 data bits plus 6 syndrome ECC (error correction code) bits allow single bit error correction
and double fault detection
— Erase sector size 256 bytes
— Automated program and erase algorithm
— User margin level setting for reads
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Device Overview MC9S12P-Family
1.3.3
•
1.3.4
•
1.3.5
•
1.3.6
•
1.3.7
•
•
•
•
•
•
On-Chip SRAM
Up to 6 Kbytes of general-purpose RAM
Main External Oscillator (XOSC)
Loop control Pierce oscillator using a 4 MHz to 16 MHz crystal
— Current gain control on amplitude output
— Signal with low harmonic distortion
— Low power
— Good noise immunity
— Eliminates need for external current limiting resistor
— Transconductance sized for optimum start-up margin for typical crystals
Internal RC Oscillator (IRC)
Trimmable internal reference clock.
— Frequency: 1 MHz
— Trimmed accuracy over –40˚C to +125˚C ambient temperature range: ±1.5%
Internal Phase-Locked Loop (IPLL)
Phase-locked-loop clock frequency multiplier
— No external components required
— Reference divider and multiplier allow large variety of clock rates
— Automatic bandwidth control mode for low-jitter operation
— Automatic frequency lock detector
— Configurable option to spread spectrum for reduced EMC radiation (frequency modulation)
— Reference clock sources:
– External 4–16 MHz resonator/crystal (XOSC)
– Internal 1 MHz RC oscillator (IRC)
System Integrity Support
Power-on reset (POR)
System reset generation
Illegal address detection with reset
Low-voltage detection with interrupt or reset
Real time interrupt (RTI)
Computer operating properly (COP) watchdog
— Configurable as window COP for enhanced failure detection
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Device Overview MC9S12P-Family
•
— Initialized out of reset using option bits located in flash memory
Clock monitor supervising the correct function of the oscillator
1.3.8
•
•
•
Timer (TIM)
8 x 16-bit channels for input capture or output compare
16-bit free-running counter with 7-bit precision prescaler
1 x 16-bit pulse accumulator
1.3.9
•
Pulse Width Modulation Module (PWM)
6 channel x 8-bit or 3 channel x 16-bit pulse width modulator
— Programmable period and duty cycle per channel
— Center-aligned or left-aligned outputs
— Programmable clock select logic with a wide range of frequencies
1.3.10
•
•
•
•
•
•
•
•
•
1 Mbit per second, CAN 2.0 A, B software compatible
— Standard and extended data frames
— 0–8 bytes data length
— Programmable bit rate up to 1 Mbps
Five receive buffers with FIFO storage scheme
Three transmit buffers with internal prioritization
Flexible identifier acceptance filter programmable as:
— 2 x 32-bit
— 4 x 16-bit
— 8 x 8-bit
Wakeup with integrated low pass filter option
Loop back for self test
Listen-only mode to monitor CAN bus
Bus-off recovery by software intervention or automatically
16-bit time stamp of transmitted/received messages
1.3.11
•
•
•
•
Controller Area Network Module (MSCAN)
Serial Communication Interface Module (SCI)
Full-duplex or single-wire operation
Standard mark/space non-return-to-zero (NRZ) format
Selectable IrDA 1.4 return-to-zero-inverted (RZI) format with programmable pulse widths
13-bit baud rate selection
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Device Overview MC9S12P-Family
•
•
•
•
Programmable character length
Programmable polarity for transmitter and receiver
Active edge receive wakeup
Break detect and transmit collision detect supporting LIN
1.3.12
•
•
•
•
•
•
Configurable 8- or 16-bit data size
Full-duplex or single-wire bidirectional
Double-buffered transmit and receive
Master or slave mode
MSB-first or LSB-first shifting
Serial clock phase and polarity options
1.3.13
•
•
On-Chip Voltage Regulator (VREG)
Linear voltage regulator with bandgap reference
Low-voltage detect (LVD) with low-voltage interrupt (LVI)
Power-on reset (POR) circuit
Low-voltage reset (LVR)
High temperature sensor
1.3.15
•
•
Analog-to-Digital Converter Module (ATD)
10-channel, 12-bit analog-to-digital converter
— 3 us single conversion time
— 8-/10-/12-bit resolution
— Left or right justified result data
— Internal oscillator for conversion in stop modes
— Wakeup from low power modes on analog comparison > or <= match
— Continuous conversion mode
— Multiple channel scans
Pins can also be used as digital I/O
1.3.14
•
•
•
•
•
Serial Peripheral Interface Module (SPI)
Background Debug (BDM)
Non-intrusive memory access commands
Supports in-circuit programming of on-chip nonvolatile memory
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Device Overview MC9S12P-Family
1.3.16
•
•
•
•
•
Debugger (DBG)
Trace buffer with depth of 64 entries
Three comparators (A, B and C)
— Comparators A compares the full address bus and full 16-bit data bus
— Exact address or address range comparisons
Two types of comparator matches
— Tagged This matches just before a specific instruction begins execution
— Force This is valid on the first instruction boundary after a match occurs
Four trace modes
Four stage state sequencer
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Device Overview MC9S12P-Family
1.4
Block Diagram
Figure 1-1 shows a block diagram of the MC9S12P-Family devices
VDDR
VSS3
Voltage Regulator
AN[9:0]
IOC0
IOC1
IOC2
IOC3
IOC4
IOC5
IOC6
IOC7
TIM
16-bit 8 channel
Timer
CPU12-V1
XTAL
VSSPLLL
RESET
TEST
Reset Generation
and Test Entry
PTE
ECLK
PTA
ECLKX2
PA[7:0]
PB[7:0]
Clock Monitor
COP Watchdog
Periodic Interrupt
Auton. Periodic Int.
8-bit 6channel
Pulse Width Modulator
PLL with Frequency
Modulation option
XIRQ
IRQ
PTB
PE0
PE1
PE2
PE3
PE4
PE5
PE6
PE7
Amplitude Controlled
Low Power Pierce
Oscillator
Interrupt Module
CAN
msCAN 2.0B
SPI
Synchronous Serial IF
RXCAN
TXCAN
MISO
SS
MOSI
SCK
SCI
Asynchronous Serial IF
RXD
TXD
PTS
EXTAL
PWM0
PWM1
PWM2
PWM3
PWM4
PWM5
PWM
PTJ (Wake-up Int)
BKGD
Debug Module
Single-wire Background 3 address breakpoints
Debug Module
1 data breakpoints
64 Byte Trace Buffer
PTT
4K bytes Data Flash
PTAD
12-bit 10-channel
Analog-Digital Converter
PTP (Wake-Up Int)
2K/4K/6K bytes RAM
VDDA
VSSA
VRH
VRL
ATD
PTM
32K/64K/96K/128K bytes Flash
3-5V IO Supply
VDDX1/VSSX1
VDDX2/VSSX2
PAD[9:0]
PT0
PT1
PT2
PT3
PT4
PT5
PT6
PT7
PP0
PP1
PP2
PP3
PP4
PP5
PP7
PM0
PM1
PM2
PM3
PM4
PM5
PS0
PS1
PS2
PS3
PJ0
PJ1
PJ2
PJ6
PJ7
Figure 1-1. MC9S12P-Family Block Diagram
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Device Overview MC9S12P-Family
1.5
Device Memory Map
Table 1-2 shows the device register memory map.
Table 1-2. Device Register Memory Map
Address
Module
Size
(Bytes)
0x0000–0x0009
PIM (port integration module)
10
0x000A–0x000B
MMC (memory map control)
2
0x000C–0x000D
PIM (port integration module)
2
0x000E–0x000F
Reserved
2
0x0010–0x0017
MMC (memory map control)
8
0x0018–0x0019
Reserved
2
0x001A–0x001B
Device ID register
2
0x001C–0x001F
PIM (port integration module)
4
0x0020–0x002F
DBG (debug module)
16
0x0030–0x0033
Reserved
4
0x0034–0x003F
CPMU (clock and power management)
12
0x0040–0x006F
TIM (timer module)
48
0x0070–0x009F
ATD (analog-to-digital converter 12 bit 10-channel)
48
0x00A0–0x00C7
PWM (pulse-width modulator 6 channels)
40
0x00C8–0x00CF
SCI (serial communications interface)
8
0x00D0–0x00D7
Reserved
8
0x00D8–0x00DF
SPI (serial peripheral interface)
8
0x00E0–0x00FF
Reserved
32
0x0100–0x0113
FTMRC control registers
20
0x0114–0x011F
Reserved
12
INT (interrupt module)
1
0x0121–0x013F
Reserved
31
0x0140–0x017F
CAN
64
0x0180–0x023F
Reserved
192
0x0240–0x027F
PIM (port integration module)
64
0x0280–0x02BF
Reserved
64
0x02C0–0x02EF
Reserved
48
0x02F0–0x02FF
CPMU (clock and power management )
16
0x0300–0x03FF
Reserved
256
0x0120
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
25
Device Overview MC9S12P-Family
NOTE
Reserved register space shown in Table 1-2 is not allocated to any module.
This register space is reserved for future use. Writing to these locations have
no effect. Read access to these locations returns zero.
Figure 1-2 shows S12P CPU and BDM local address translation to the global memory map. It indicates
also the location of the internal resources in the memory map. Table 1-3. shows the mapping of D-Flash
and unpaged P-Flash memory. The whole 256K global memory space is visible through the P-Flash
window located in the 64k local memory map located at 0x8000 - 0xBFFF using the PPAGE register.
Table 1-3. MC9S12P -Family mapping for D-Flash and unpaged P-Flash
Local 64K memory map
Global 256K memory map
0x0400 - 0x13FF
0x0_4400 - 0x0_53FF
0x1400 - 0x27FF(1)
0x3_1400 -0x3_27FF(2)
0x4000 - 0x7FFF
0x3_4000 - 0x3_7FFF
D-Flash
P-Flash
0xC000 - 0xFFFF
0x3_C000 - 0x3_FFFF
1. 0x2FFF for MC9S12P64 because of 4K RAM size
2. 0x3_2FFF for MC9S12P64 because of 4K RAM size
Table 1-4. Derivatives
Feature
MC9S12P32
MC9S12P64
MC9S12P96
MC9S12P128
P-Flash size
32KB
64KB
96KB
128KB
PF_LOW
PPAGES
0x3_8000
0x0E - 0x0F
0x3_0000
0x0C - 0x0F
0x2_8000
0x0A - 0x0F
0x2_0000
0x08 - 0x0F
RAMSIZE
2KB
4KB
6KB
RAM_LOW
0x0_3800
0x0_3000
0x0_2800
S12P-Family Reference Manual, Rev. 1.13
26
Freescale Semiconductor
Device Overview MC9S12P-Family
Figure 1-2. MC9S12P-Family Global Memory Map
CPU and BDM
Local Memory Map
Global Memory Map
0x0000
0x0400
0x1400
RAM_LOW
Unpaged P-Flash
0x0_4000
NVM Resources
D-Flash
0x0_5400
NVM Resources
0x4000
(PPAGE 0x01)
RAMSIZE
0x0_4400
RAM
RAMSIZE
Unimplemented Area
D-Flash
RAM
REGISTERS
(PPAGE 0x00)
0x0_0000
REGISTERS
PF_LOW=0x0_8000
P-Flash
10 *16K paged
0x8000
(PPAGE 0x02-0x0B))
Unpaged P-Flash
PF_LOW=0x3_0000
0 0 0 0 P3 P2 P1 P0
Unpaged P-Flash
PPAGE
Unpaged P-Flash
0xC000
(PPAGE 0x0E)
PF_LOW=0x3_8000
Unpaged P-Flash
Unpaged P-Flash
(PPAGE 0x0F)
PF_LOW=0x3_C000
0xFFFF
0x3_FFFF
(PPAGE 0x0D)
PF_LOW=0x3_4000
(PPAGE 0x0C)
P-Flash window
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
27
Device Overview MC9S12P-Family
1.6
Part ID Assignments
The part ID is located in two 8-bit registers PARTIDH and PARTIDL (addresses 0x001A and 0x001B).
The read-only value is a unique part ID for each revision of the chip. Table 1-5 shows the assigned part ID
number and Mask Set number.
The Version ID in Table 1-5. is a word located in a flash information row. The version ID number indicates
a specific version of internal NVM controller.
Table 1-5. Assigned Part ID Numbers
Device
Mask Set Number
Part ID(1)
Version ID
MC9S12P128
0M01N
$3980
$FF
MC9S12P96
0M01N
$3980
$FF
MC9S12P64
0M01N
$3980
$FF
MC9S12P32
0M01N
$3980
1. The coding is as follows:
Bit 15-12: Major family identifier
Bit 11-6: Minor family identifier
Bit 5-4: Major mask set revision number including FAB transfers
Bit 3-0: Minor — non full — mask set revision
1.7
$FF
Signal Description
This section describes signals that connect off-chip. It includes a pinout diagram, a table of signal
properties, and detailed discussion of signals. It is built from the signal description sections of the
individual IP blocks on the device.
S12P-Family Reference Manual, Rev. 1.13
28
Freescale Semiconductor
Device Overview MC9S12P-Family
1.7.1
Device Pinout
80
79
78
77
76
75
74
73
72
71
70
69
68
67
66
65
64
63
62
61
PP4/KWP4/PWM4
PP5/KPW5/PWM5
PP7/KPW7
VDDX1
VSSX1
PM0/RXCAN0
PM1/TXCAN0
PM2/MISO0
PM3/SS0
PM4/MOSI0
PM5/SCK0
PJ6/KWJ6
PJ7/KWJ7
TEST
PS3
PS2
PS1/TXD0
PS0/RXD0
VSSA
VRL
Figure 1-3. MC9S12P-Family 80 QFP pinout
MC9S12P-Family
80 QFP
Pins shown in BOLD are
not available on the
64 LQFP package
60
59
58
57
56
55
54
53
52
51
50
49
48
47
46
45
44
43
42
41
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
VRH
VDDA
PAD07/AN07
PAD06/AN06
PAD05/AN05
PAD04/AN04
PAD03/AN03
PAD02/AN02
PAD01/AN01
PAD00/AN00
PAD09/AN09
PAD08/AN08
PA7
PA6
PA5
PA4
PA3
PA2
PA1
PA0
PB5
PB6
PB7
PE7
PE6
PE5
ECLK/PE4
VSSX2
VDDX2
RESET
VDDR
VSS3
VSSPLL
EXTAL
XTAL
KWJ2/PJ2
PE3
PE2
IRQ/PE1
XIRQ/PE0
PWM3/KWP3/PP3
PWM2/KWP2/PP2
PWM1/KWP1/PP1
PWM0/KWP0/PP0
PWM0/IOC0/PT0
IOC1/PT1
IOC2/PT2
IOC3/PT3
KWJ0/PJ0
KWJ1/PJ1
PWM4/IOC4/PT4
API_EXTCLK/PWM5/IOC5/PT5
IOC6/PT6
IOC7/PT7
MODC/BKGD
PB0
PB1
PB2
PB3
PB4
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
29
Device Overview MC9S12P-Family
64
63
62
61
60
59
58
57
56
55
54
53
52
51
50
49
PP5/PWM5/KWP5
PP7/KWP7
VDDX1
VSSX1
PM0/RXCAN0
PM1/TXCAN0
PM2/MISO0
PM3/SS0
PM4/MOSI0
PM5/SCK0
TEST
PS3
PS2
PS1/TXD0
PS0/RXD0
VSSA/VRL
Figure 1-4. MC9S12P-Family 64 LQFP pinout
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
MC9S12P-Family
64 LQFP
Pins shown in BOLD are
not available on the
48 QFN package
48
47
46
45
44
43
42
41
40
39
38
37
36
35
34
33
VRH
VDDA
PAD07/AN07
PAD06/AN06
PAD05/AN05
PAD04/AN04
PAD03/AN03
PAD02/AN02
PAD01/AN01
PAD00/AN00
PAD09/AN09
PAD08/AN08
PA3
PA2
PA1
PA0
PB5
PB6
PB7
PE7
ECLK/PE4
VSSX2
VDDX2
RESET
VDDR
VSS3
VSSPLL
EXTAL
XTAL
KWJ2/PJ2
IRQ/PE1
XIRQ/PE0
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
PWM3/KWP3/PP3
PWM2/KWP2/PP2
PWM1/KWP1/PP1
PWM0/KWP0/PP0
PWM0/IOC0/PT0
IOC1/PT1
IOC2/PT2
IOC3/PT3
KWJ0/PJ0
KWJ1/PJ1
PWM4/IOC4/PT4
API_EXTCLK/PWM5/IOC5/PT5
IOC6/PT6
IOC7/PT7
MODC/BKGD
PB0
S12P-Family Reference Manual, Rev. 1.13
30
Freescale Semiconductor
Device Overview MC9S12P-Family
48
47
46
45
44
43
42
41
40
39
38
37
VDDX1
VSSX1
PM0/RXCAN0
PM1/TXCAN0
PM2/MISO0
PM3/SS0
PM4/MOSI0
PM5/SCK0
TEST
PS1/TXD0
PS0/RXD0
VSSA/VRL
Figure 1-5. MC9S12P-Family 48 QFN pinout
1
2
3
4
5
6
7
8
9
10
11
12
MC9S12P-Family
48 QFN
36
35
34
33
32
31
30
29
28
27
26
25
VDDA/VRH
PAD07/AN07
PAD06/AN06
PAD05/AN05
PAD04/AN04
PAD03/AN03
PAD02/AN02
PAD01/AN01
PAD00/AN00
PAD09/AN09
PAD08/AN08
PE0/XIRQ
PE7
ECLK/PE4
VSSX2
VDDX2
RESET
VDDR
VSS3
VSSPLL
EXTAL
XTAL
KWJ2/PJ2
IRQ/PE1
13
14
15
16
17
18
19
20
21
22
23
24
PWM3/KWP3/PP3
PWM2/KWP2/PP2
PWM1/KWP1/PP1
PWM0/IOC0/PT0
IOC1/PT1
IOC2/PT2
IOC3/PT3
PWM4/IOC4/PT4
API_EXTCLK/PWM5/IOC5/PT5
IOC6/PT6
IOC7/PT7
MODC/BKGD
1.7.2
Pin Assignment Overview
Table 1-6 provides a summary of which Ports are available for each package option. Routing of pin
functions is summarized in Table 1-7.
Table 1-6. Port Availability by Package Option
Port
80 QFP
64 LQFP
48 QFN
Port AD/ADC Channels
10/10
10/10
10/10
Port A pins
8
4
0
Port B pins
8
4
0
Port E pins inc. IRQ/XIRQ input only
8
4
4
Port J
5
3
1
Port M
6
6
6
Port P
7
6
3
Port S
4
4
2
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
31
Device Overview MC9S12P-Family
Table 1-6. Port Availability by Package Option
Port
80 QFP
64 LQFP
48 QFN
Port T
8
8
8
Sum of Ports
64
49
34
I/O Power Pairs VDDX/VSSX
2/2
2/2
2/2
Table 1-7. Peripheral - Port Routing Options(1)
PWM0
PT0
PT4
PWM4
PWM5
O
O
PT5
O
1. “O” denotes a possible rerouting under software
control
Table 1-8 provides a pin out summary listing the availability and functionality of individual pins for each
package option.
S12P-Family Reference Manual, Rev. 1.13
32
Freescale Semiconductor
Freescale Semiconductor
Table 1-8. Pin-Out Summary(1)
Package Pin
Function
QFP
80
LQFP
64
QFN
48
S12P-Family Reference Manual, Rev. 1.13
Pin
2nd
Func.
3rd
Func.
1
1
1
PP3
KWP3
PWM3
2
2
2
PP2
KWP2
3
3
3
PP1
4
4
-
5
5
6
Power
Supply
Internal Pull
Resistor
Description
VDDX
PERP/PPSP
Disabled
Port P I/O, interrupt,
PWM channel
PWM2
VDDX
PERP/PPSP
Disabled
Port P I/O, interrupt,
PWM channel
KWP1
PWM1
VDDX
PERP/PPSP
Disabled
Port P I/O, interrupt,
PWM channel
PP0
KWP0
PWM0
VDDX
PERP/PPSP
Disabled
Port P I/O, interrupt,
PWM/ channel
4
PT0
IOC0
PWM0
VDDX
PERT/PPST
Disabled
Port T I/O, TIM channel
6
5
PT1
IOC1
—
VDDX
PERT/PPST
Disabled
Port T I/O, TIM channel
7
7
6
PT2
IOC2
—
VDDX
PERT/PPST
Disabled
Port T I/O, TIM channel
8
8
7
PT3
IOC3
—
VDDX
PERT/PPST
Disabled
Port T I/O, TIM channel
9
9
-
PJ0
KWJ0
—
VDDX
PERJ/PPSJ
Up
Port J I/O, interrupt
10
10
-
PJ1
KWJ1
—
VDDX
PERJ/PPSJ
Up
Port J I/O, interrupt
11
11
8
PT4
IOC4
PWM4
VDDX
PERT/PPST
Disabled
Port T I/O, PWM/TIM
channel
12
12
9
PT5
IOC5
PWM5
or
API_EX
TCLK
VDDX
PERT/PPST
Disabled
Port T I/O, PWM/TIM
channel, API output
13
13
10
PT6
IOC6
VDDX
PERT/PPST
Disabled
Port T I/O, channel of
TIM
14
14
11
PT7
IOC7
VDDX
PERT/PPST
Disabled
Port T I/O, channel of
TIM
15
15
12
BKGD
MODC
VDDX
Always on
Up
—
Background debug
Device Overview MC9S12P-Family
33
CTRL
Reset
State
Freescale Semiconductor
Table 1-8. Pin-Out Summary(1)
Package Pin
Function
QFP
80
LQFP
64
QFN
48
S12P-Family Reference Manual, Rev. 1.13
Pin
2nd
Func.
3rd
Func.
16
16
-
PB0
—
—
17
-
-
PB1
—
18
-
-
PB2
19
-
-
20
-
21
Power
Supply
Internal Pull
Resistor
Description
VDDX
PUCR
Disabled
Port B I/O
—
VDDX
PUCR
Disabled
Port B I/O
—
—
VDDX
PUCR
Disabled
Port B I/O
PB3
—
—
VDDX
PUCR
Disabled
Port B I/O
-
PB4
—
—
VDDX
PUCR
Disabled
Port B I/O
17
-
PB5
—
—
VDDX
PUCR
Disabled
Port B I/O
22
18
-
PB6
—
—
VDDX
PUCR
Disabled
Port B I/O
23
19
-
PB7
—
—
VDDX
PUCR
Disabled
Port B I/O
24
20
13
PE7
ECLKX2
—
VDDX
PUCR
Up
Port E I/O
25
-
-
PE6
—
—
VDDX
While RESET pin
is low: down
Port E I/O
26
-
-
PE5
—
—
VDDX
While RESET pin
is low: down
Port E I/O
27
21
14
PE4
ECLK
—
VDDX
PUCR
Up
Port E I/O, bus clock
output
28
22
15
VSSX2
—
—
—
—
—
—
29
23
16
VDDX2
—
—
—
—
—
—
30
24
17
RESET
—
—
VDDX
31
25
18
VDDR
—
—
—
—
—
—
32
26
19
VSS3
—
—
—
—
—
—
33
27
20
VSSPLL
—
—
—
—
—
—
34
28
21
EXTAL
—
—
VDDP
LL
NA
NA
Oscillator pin
PULLUP
External reset
34
Device Overview MC9S12P-Family
CTRL
Reset
State
Freescale Semiconductor
Table 1-8. Pin-Out Summary(1)
Package Pin
Function
QFP
80
LQFP
64
QFN
48
S12P-Family Reference Manual, Rev. 1.13
Pin
2nd
Func.
3rd
Func.
35
29
22
XTAL
—
—
36
30
23
PJ2
KWJ2
37
-
-
PE3
38
-
-
39
31
40
Power
Supply
Internal Pull
Resistor
Description
VDDP
LL
NA
NA
—
VDDX
PERJ/PPSJ
Up
—
—
VDDX
PUCR
Up
Port E I/O
PE2
—
—
VDDX
PUCR
Up
Port E I/O
24
PE1
IRQ
—
VDDX
PUCR
Up
Port E Input, maskable
interrupt
32
25
PE0
XIRQ
—
VDDX
PUCR
Up
Port E Input, nonmaskable interrupt
41
33
-
PA0
—
—
VDDX
PUCR
Disabled
Port A I/O
42
34
-
PA1
—
—
VDDX
PUCR
Disabled
Port A I/O
43
35
-
PA2
—
—
VDDX
PUCR
Disabled
Port A I/O
44
36
-
PA3
—
—
VDDX
PUCR
Disabled
Port A I/O
45
-
-
PA4
—
—
VDDX
PUCR
Disabled
Port A I/O
46
-
-
PA5
—
—
VDDX
PUCR
Disabled
Port A I/O
47
-
-
PA6
—
—
VDDX
PUCR
Disabled
Port A I/O
48
-
-
PA7
—
—
VDDX
PUCR
Disabled
Port A I/O
49
37
26
PAD08
AN08
—
VDDA
PER1AD
Disabled
Port AD I/O,
analog input of ATD
50
38
27
PAD09
AN09
—
VDDA
PER1AD
Disabled
Port AD I/O,
analog input of ATD
51
39
28
PAD00
AN00
—
VDDA
PER1AD
Disabled
Port AD I/O,
analog input of ATD
52
40
29
PAD01
AN01
—
VDDA
PER1AD
Disabled
Port AD I/O,
analog input of ATD
Oscillator pin
Port J I/O, interrupt
Device Overview MC9S12P-Family
35
CTRL
Reset
State
Package Pin
Function
QFP
80
LQFP
64
QFN
48
S12P-Family Reference Manual, Rev. 1.13
Pin
2nd
Func.
3rd
Func.
53
41
30
PAD02
AN02
—
54
42
31
PAD03
AN03
55
43
32
PAD04
56
44
33
57
45
58
Power
Supply
Internal Pull
Resistor
Description
Freescale Semiconductor
CTRL
Reset
State
VDDA
PER1AD
Disabled
Port AD I/O,
analog input of ATD
—
VDDA
PER1AD
Disabled
Port AD I/O,
analog input of ATD
AN04
—
VDDA
PER1AD
Disabled
Port AD I/O,
analog input of ATD
PAD05
AN05
—
VDDA
PER1AD
Disabled
Port AD I/O,
analog input of ATD
34
PAD06
AN06
—
VDDA
PER1AD
Disabled
Port AD I/O,
analog input of ATD
46
35
PAD07
AN07
—
VDDA
PER1AD
Disabled
Port AD I/O,
analog input of ATD
59
47
36
VDDA
—
—
—
—
—
—
60
48
36
VRH(2)
—
—
—
—
—
—
61
49
37
VRL(3)
—
—
—
—
—
—
62
49
37
VSSA
—
—
—
—
—
—
63
50
38
PS0
RXD
—
VDDX
PERS/PPSS
Up
Port S I/O, RXD of SCI
64
51
39
PS1
TXD
—
VDDX
PERS/PPSS
Up
Port S I/O, TXD of SCI
65
52
-
PS2
—
VDDX
PERS/PPSS
Up
Port S I/O
66
53
-
PS3
—
VDDX
PERS/PPSS
Up
Port S I/O
67
54
40
TEST
—
—
N.A.
RESET pin
DOWN
Test input
68
-
-
PJ7
KWJ7
—
VDDX
PERJ/PPSJ
Up
Port J I/O, interrupt
69
-
-
PJ6
KWJ6
—
VDDX
PERJ/PPSJ
Up
Port J I/O, interrupt
70
55
41
PM5
SCK
—
VDDX
PERM/PPSM
Disabled
Port M I/O, MISO of SPI
Device Overview MC9S12P-Family
36
Table 1-8. Pin-Out Summary(1)
Freescale Semiconductor
Table 1-8. Pin-Out Summary(1)
Package Pin
Function
QFP
80
LQFP
64
QFN
48
S12P-Family Reference Manual, Rev. 1.13
Pin
2nd
Func.
3rd
Func.
71
56
42
PM4
MOSI
—
72
57
43
PM3
SS
73
58
44
PM2
MISO
74
59
45
PM1
75
60
46
76
61
77
Power
Supply
Internal Pull
Resistor
Description
CTRL
Reset
State
VDDX
PERM/PPSM
Disabled
Port M I/O, MOSI of SPI
—
VDDX
PERM/PPSM
Disabled
Port M I/O, SCK of SPI
—
VDDX
PERM/PPSM
Disabled
Port M I/O, SS of SPI0
TXCAN
VDDX
PERM/PPSM
Disabled
Port M I/O, TX of CAN
PM0
RXCAN
VDDX
PERM/PPSM
Disabled
Port M I/O, RX of CAN
47
VSSX1
—
—
—
—
—
—
62
48
VDDX1
—
—
—
—
—
—
78
63
-
PP7
KWP7
VDDX
PERP/PPSP
Disabled
Port P I/O, interrupt
79
64
-
PP5
KWP5
PWM5
VDDX
PERP/PPSP
Disabled
Port P I/O, interrupt,
PWM channel
80
-
-
PP4
KWP4
PWM4
VDDX
PERP/PPSP
Disabled
Port P I/O, interrupt,
PWM channel
1. Table shows a superset of pin functions. Not all functions are available on all derivatives
2. VRH and VDDA share single pin on 48 pin package option
3. VRL and VSSA share single pin on 64 and 48 pin package option
37
Device Overview MC9S12P-Family
NOTE
For devices assembled in 48-pin and 64-pin packages all non-bonded out pins should be configured as
outputs after reset in order to avoid current drawn from floating inputs. Refer to Table 1-8 for affected
pins.
Device Overview MC9S12P-Family
1.7.3
1.7.3.1
Detailed Signal Descriptions
EXTAL, XTAL — Oscillator Pins
EXTAL and XTAL are the crystal driver and external clock pins. On reset all the device clocks are derived
from the internal reference clock. XTAL is the oscillator output.
1.7.3.2
RESET — External Reset Pin
The RESET pin is an active low bidirectional control signal. It acts as an input to initialize the MCU to a
known start-up state, and an output when an internal MCU function causes a reset. The RESET pin has an
internal pull-up device.
1.7.3.3
TEST — Test Pin
This input only pin is reserved for factory test. This pin has an internal pull-down device.
NOTE
The TEST pin must be tied to VSSX in all applications.
1.7.3.4
BKGD / MODC — Background Debug and Mode Pin
The BKGD/MODC pin is used as a pseudo-open-drain pin for the background debug communication. It
is used as a MCU operating mode select pin during reset. The state of this pin is latched to the MODC bit
at the rising edge of RESET. The BKGD pin has an internal pull-up device.
1.7.3.5
PAD[9:0] / AN[9:0] — Port AD Input Pins of ATD
PAD[9:0] are general-purpose input or output pins and analog inputs AN[9:0] of the analog-to-digital
converter ATD.
1.7.3.6
PA[7:0] — Port A I/O Pins
PA[7:0] are general-purpose input or output pins.
1.7.3.7
PB[7:0] — Port B I/O Pins
PB[7:0] are general-purpose input or output pins.
1.7.3.8
PE7 — Port E I/O Pin 7 / ECLKX2
PE7 is a general-purpose input or output pin. An internal pull-up is enabled during reset. It can be
configured to output ECLKX2.
1.7.3.9
PE[6:5] — Port E I/O Pin 6-5
PE[6:5] are a general-purpose input or output pins.
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Device Overview MC9S12P-Family
1.7.3.10
PE4 / ECLK — Port E I/O Pin 4
PE4 is a general-purpose input or output pin. It can be configured to drive the internal bus clock ECLK.
ECLK can be used as a timing reference. The ECLK output has a programmable prescaler.
1.7.3.11
PE[3:2] — Port E I/O Pin 3
PE[3:2] are a general-purpose input or output pins.
1.7.3.12
PE1 / IRQ — Port E Input Pin 1
PE1 is a general-purpose input pin and the maskable interrupt request input that provides a means of
applying asynchronous interrupt requests. This will wake up the MCU from stop or wait mode.
1.7.3.13
PE0 / XIRQ — Port E Input Pin 0
PE0 is a general-purpose input pin and the non-maskable interrupt request input that provides a means of
applying asynchronous interrupt requests. This will wake up the MCU from stop or wait mode. The XIRQ
interrupt is level sensitive and active low. As XIRQ is level sensitive, while this pin is low the MCU will
not enter STOP mode.
1.7.3.14
PJ[7:6, 2:0] / KWJ[7:6, 2:0] — Port J I/O Pins 7-6, 2-0
PJ[7:6, 2:0] are a general-purpose input or output pins. They can be configured as keypad wakeup inputs.
1.7.3.15
PM[7:6] — Port M I/O Pins 7-6
PM[7:6] are a general-purpose input or output pins.
1.7.3.16
PM5 / SCK — Port M I/O Pin 5
PM5 is a general-purpose input or output pin. It can be configured as the serial clock pin SCK of the serial
peripheral interface (SPI).
1.7.3.17
PM4 / MOSI — Port M I/O Pin 4
PM4 is a general-purpose input or output pin. It can be configured as the master output (during master
mode) or slave input pin (during slave mode) MOSI for the serial peripheral interface (SPI).
1.7.3.18
PM3 / SS — Port M I/O Pin 3
PM3 is a general-purpose input or output pin.It can be configured as the slave select pin SS of the serial
peripheral interface (SPI).
1.7.3.19
PM2 / MISO— Port M I/O Pin 3
PM2 is a general-purpose input or output pin. It can be configured as the master input (during master
mode) or slave output pin (during slave mode) MISO for the serial peripheral interface (SPI)
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Device Overview MC9S12P-Family
1.7.3.20
PM1 / TXCAN — Port M I/O Pin 1
PM1 is a general-purpose input or output pin. It can be configured as the transmit pin TXCAN of the
scalable controller area network controller (CAN).
1.7.3.21
PM0 / RXCAN — Port M I/O Pin 0
PM0 is a general-purpose input or output pin. It can be configured as the receive pin RXCAN of the
scalable controller area network controller (CAN).
1.7.3.22
PP[5:0] / KWP[5:0] / PWM[5:0] — Port P I/O Pins 5-0
PP[5:0] are a general-purpose input or output pins. They can be configured as keypad wakeup inputs. They
can be configured as pulse width modulator (PWM) channel 5-0 output
1.7.3.23
PP7 / KWP7 — Port P I/O Pin 7
PP7 is a general-purpose input or output pin. It can be configured as a keypad wakeup input.
1.7.3.24
PS3 — Port S I/O Pin 3
PS3 is a general-purpose input or output pin.
1.7.3.25
PS2 — Port S I/O Pin 2
PS2 is a general-purpose input or output pin.
1.7.3.26
PS1 / TXD — Port S I/O Pin 1
PS1 is a general-purpose input or output pin. It can be configured as the transmit pin TXD of serial
communication interface (SCI).
1.7.3.27
PS0 / RXD — Port S I/O Pin 0
PS0 is a general-purpose input or output pin. It can be configured as the receive pin RXD of serial
communication interface (SCI).
1.7.3.28
PT[7:6] / IOC[7:6] — Port T I/O Pins 7-6
PT[7:6] are general-purpose input or output pins. They can be configured as timer (TIM) channel 7-6.
1.7.3.29
PT5 / IOC5 / PWM5 / API_EXTCLK — Port T I/O Pin 5
PT5 is a general-purpose input or output pin. It can be configured as timer (TIM) channel 5, pulse width
modulator (PWM) output 5 or as the output of the API_EXTCLK.
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Device Overview MC9S12P-Family
1.7.3.30
PT4 / IOC4 / PWM4 — Port T I/O Pin 4
PT4 is a general-purpose input or output pin. It can be configured as timer (TIM) channel 4 or pulse width
modulator (PWM) output 4.
1.7.3.31
PT[3:1] / IOC[3:1] — Port T I/O Pin [3:1]
PT[3:1] are a general-purpose input or output pins. They can be configured as timer (TIM) channels 3-1.
1.7.3.32
PT0 / IOC0 / PWM0 — Port T I/O Pin 0
PT0 is a general-purpose input or output pin. It can be configured as timer (TIM) channel 0 or pulse width
modulator (PWM) output 0.
1.7.4
Power Supply Pins
MC9S12P-Family power and ground pins are described below.
Because fast signal transitions place high, short-duration current demands on the power supply, use bypass
capacitors with high-frequency characteristics and place them as close to the MCU as possible.
NOTE
All VSS pins must be connected together in the application.
1.7.4.1
VDDX[2:1], VSSX[2:1] — Power and Ground Pins for I/O Drivers
External power and ground for I/O drivers. Bypass requirements depend on how heavily the MCU pins are
loaded. All VDDX pins are connected together internally. All VSSX pins are connected together
internally.
1.7.4.2
VDDR — Power Pin for Internal Voltage Regulator
Power supply input to the internal voltage regulator.
1.7.4.3
VSS3 — Core Ground Pin
The voltage supply of nominally 1.8V is derived from the internal voltage regulator. The return current
path is through the VSS3 pin. No static external loading of these pins is permitted.
1.7.4.4
VDDA, VSSA — Power Supply Pins for ATD and Voltage Regulator
These are the power supply and ground input pins for the analog-to-digital converter and the voltage
regulator.
1.7.4.5
VRH, VRL — ATD Reference Voltage Input Pins
VRH and VRL are the reference voltage input pins for the analog-to-digital converter.
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Device Overview MC9S12P-Family
1.7.4.6
VSSPLL — Ground Pin for PLL
This pin provides ground for the oscillator and the phased-locked loop. The voltage supply of nominally
1.8V is derived from the internal voltage regulator.
1.7.4.7
Power and Ground Connection Summary
Table 1-9. Power and Ground Connection Summary
1.8
Mnemonic
Nominal
Voltage
VDDR
5.0 V
External power supply to internal voltage
regulator
VDDX[2:1]
5.0 V
VSSX[2:1]
0V
External power and ground, supply to pin
drivers
VDDA
5.0 V
VSSA
0V
VRL
0V
VRH
5.0 V
VSS3
0V
Internal power and ground generated by
internal regulator for the internal core.
VSSPLL
0V
Provides operating voltage and ground for
the phased-locked loop. This allows the
supply voltage to the PLL to be bypassed
independently. Internal power and ground
generated by internal regulator.
Description
Operating voltage and ground for the
analog-to-digital converters and the
reference for the internal voltage regulator,
allows the supply voltage to the A/D to be
bypassed independently.
Reference voltages for the analog-to-digital
converter.
System Clock Description
For the system clock description please refer to chapter Chapter 7, “S12 Clock, Reset and Power
Management Unit (S12CPMU).
1.9
Modes of Operation
The MCU can operate in different modes. These are described in 1.9.1 Chip Configuration Summary.
The MCU can operate in different power modes to facilitate power saving when full system performance
is not required. These are described in 1.9.2 Low Power Operation.
Some modules feature a software programmable option to freeze the module status whilst the background
debug module is active to facilitate debugging.
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Device Overview MC9S12P-Family
1.9.1
Chip Configuration Summary
The different modes and the security state of the MCU affect the debug features (enabled or disabled).
The operating mode out of reset is determined by the state of the MODC signal during reset (see Table 110). The MODC bit in the MODE register shows the current operating mode and provides limited mode
switching during operation. The state of the MODC signal is latched into this bit on the rising edge of
RESET.
Table 1-10. Chip Modes
Chip Modes
1.9.1.1
MODC
Normal single chip
1
Special single chip
0
Normal Single-Chip Mode
This mode is intended for normal device operation. The opcode from the on-chip memory is being
executed after reset (requires the reset vector to be programmed correctly). The processor program is
executed from internal memory.
1.9.1.2
Special Single-Chip Mode
This mode is used for debugging single-chip operation, boot-strapping, or security related operations. The
background debug module BDM is active in this mode. The CPU executes a monitor program located in
an on-chip ROM. BDM firmware waits for additional serial commands through the BKGD pin.
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43
Device Overview MC9S12P-Family
1.9.2
Low Power Operation
The MC9S12P has two static low-power modes Pseudo Stop and Stop Mode. For a detailed description
refer to S12CPMU section.
1.10
Security
The MCU security mechanism prevents unauthorized access to the Flash memory. Refer to Section 5.4.1
Security and Section 13.5 Security
1.11
Resets and Interrupts
Consult the S12 CPU manual and the S12SINT section for information on exception processing.
1.11.1
Resets
Table 1-11. lists all Reset sources and the vector locations. Resets are explained in detail in the Section
Chapter 7 S12 Clock, Reset and Power Management Unit (S12CPMU)
Table 1-11. Reset Sources and Vector Locations
1.11.2
Vector Address
Reset Source
CCR
Mask
Local Enable
$FFFE
Power-On Reset (POR)
None
None
$FFFE
Low Voltage Reset (LVR)
None
None
$FFFE
External pin RESET
None
None
$FFFE
Illegal Address Reset
None
None
$FFFC
Clock monitor reset
None
OSCE Bit in CPMUOSC register
$FFFA
COP watchdog reset
None
CR[2:0] in CPMUCOP register
Interrupt Vectors
Table 1-12 lists all interrupt sources and vectors in the default order of priority. The interrupt module (see
Section Chapter 4 Interrupt Module (S12SINTV1)) provides an interrupt vector base register (IVBR)
to relocate the vectors.
Table 1-12. Interrupt Vector Locations (Sheet 1 of 3)
Vector Address(1)
Interrupt Source
CCR
Mask
Local Enable
Wake up
Wakeup
from STOP from WAIT
Vector base + $F8
Unimplemented instruction trap
None
None
-
-
Vector base+ $F6
SWI
None
None
-
-
Vector base+ $F4
XIRQ
X Bit
None
Yes
Yes
Vector base+ $F2
IRQ
I bit
IRQCR (IRQEN)
Yes
Yes
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Device Overview MC9S12P-Family
Table 1-12. Interrupt Vector Locations (Sheet 2 of 3)
Vector Address(1)
Interrupt Source
CCR
Mask
Local Enable
Wake up
Wakeup
from STOP from WAIT
Vector base+ $F0
RTI timeout interrupt
I bit
CPMUINT (RTIE)
7.6 Interrupts
Vector base+ $EE
TIM timer channel 0
I bit
TIE (C0I)
No
Yes
Vector base + $EC
TIM timer channel 1
I bit
TIE (C1I)
No
Yes
Vector base+ $EA
TIM timer channel 2
I bit
TIE (C2I)
No
Yes
Vector base+ $E8
TIM timer channel 3
I bit
TIE (C3I)
No
Yes
Vector base+ $E6
TIM timer channel 4
I bit
TIE (C4I)
No
Yes
Vector base+ $E4
TIM timer channel 5
I bit
TIE (C5I)
No
Yes
Vector base + $E2
TIM timer channel 6
I bit
TIE (C6I)
No
Yes
Vector base+ $E0
TIM timer channel 7
I bit
TIE (C7I)
No
Yes
Vector base+ $DE
TIM timer overflow
I bit
TSRC2 (TOF)
No
Yes
Vector base+ $DC
TIM Pulse accumulator A overflow
I bit
PACTL (PAOVI)
No
Yes
Vector base + $DA
TIM Pulse accumulator input edge
I bit
PACTL (PAI)
No
Yes
Vector base + $D8
SPI
I bit
SPICR1 (SPIE, SPTIE)
No
Yes
Vector base+ $D6
SCI
I bit
SCICR2
(TIE, TCIE, RIE, ILIE)
Yes
Yes
Yes
Yes
Yes
Yes
Reserved
Vector base + $D4
Vector base + $D2
ATD
I bit
Reserved
Vector base + $D0
Vector base + $CE
ATDCTL2 (ASCIE)
Port J
I bit
Vector base + $CC
to
Vector base + $CA
PIEJ (PIEJ7-PIEJ6, PIEJ2PIEJ0)
Reserved
Vector base + $C8
Oscillator status interrupt
I bit
CPMUINT (OSCIE)
No
No
Vector base + $C6
PLL lock interrupt
I bit
CPMUINT (LOCKIE)
No
No
Vector base + $C4
to
Vector base + $BC
Reserved
Vector base + $BA
FLASH error
I bit
FERCNFG (SFDIE, DFDIE)
No
No
Vector base + $B8
FLASH command
I bit
FCNFG (CCIE)
No
Yes
Vector base + $B6
CAN wake-up
I bit
CANRIER (WUPIE)
Vector base + $B4
CAN errors
I bit
CANRIER (CSCIE, OVRIE)
Vector base + $B2
CAN receive
I bit
CANRIER (RXFIE)
Vector base + $B0
CAN transmit
I bit
CANTIER (TXEIE[2:0])
8.4.7 Interrupts
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Device Overview MC9S12P-Family
Table 1-12. Interrupt Vector Locations (Sheet 3 of 3)
Vector Address(1)
Interrupt Source
CCR
Mask
Vector base + $AE
to
Vector base + $90
Local Enable
Wake up
Wakeup
from STOP from WAIT
Reserved
Vector base + $8E
Port P interrupt
I bit
PIEP (PIEP7,PIEP5-PIEP0)
Yes
Yes
Vector base+ $8C
PWM emergency shutdown
I bit
PWMSDN (PWMIE)
No
Yes
Vector base + $8A
Low-voltage interrupt (LVI)
I bit
CPMUCTRL (LVIE)
No
Yes
Vector base + $88
Autonomous periodical interrupt
(API)
I bit
CPMUAPICTRL (APIE)
Yes
Yes
Vector base + $86
High temperature interrupt
I bit
CPMUHTCL (HTIE)
No
Yes
Vector base + $84
ATD compare interrupt
I bit
ATDCTL2 (ACMPIE)
Yes
Yes
-
-
Reserved
Vector base + $82
Vector base + $80
1. 16 bits vector address based
1.11.3
Spurious interrupt
—
None
Effects of Reset
When a reset occurs, MCU registers and control bits are initialized. Refer to the respective block sections
for register reset states.
On each reset, the Flash module executes a reset sequence to load Flash configuration registers.
1.11.3.1
Flash Configuration Reset Sequence Phase
On each reset, the Flash module will hold CPU activity while loading Flash module registers from the
Flash memory. If double faults are detected in the reset phase, Flash module protection and security may
be active on leaving reset. This is explained in more detail in the Flash module section 13.6 Initialization.
1.11.3.2
Reset While Flash Command Active
If a reset occurs while any Flash command is in progress, that command will be immediately aborted. The
state of the word being programmed or the sector/block being erased is not guaranteed.
1.11.3.3
I/O Pins
Refer to the PIM section for reset configurations of all peripheral module ports.
1.11.3.4
Memory
The RAM arrays are not initialized out of reset.
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Device Overview MC9S12P-Family
1.12
COP Configuration
The COP time-out rate bits CR[2:0] and the WCOP bit in the CPMUCOP register at address 0x003C are
loaded from the Flash register FOPT. See Table 1-13 and Table 1-14 for coding. The FOPT register is
loaded from the Flash configuration field byte at global address 0x3_FF0E during the reset sequence.
Table 1-13. Initial COP Rate Configuration
NV[2:0] in
FOPT Register
CR[2:0] in
COPCTL Register
000
111
001
110
010
101
011
100
100
011
101
010
110
001
111
000
Table 1-14. Initial WCOP Configuration
1.13
NV[3] in
FOPT Register
WCOP in
COPCTL Register
1
0
0
1
ATD External Trigger Input Connection
The ATD module includes external trigger inputs ETRIG0 and ETRIG1. The external trigger allows the
user to synchronize ATD conversion to external trigger events. Table 1-15 shows the connection of the
external trigger inputs.
Table 1-15. ATD External Trigger Sources
External Trigger
Input
Connectivity
ETRIG0
PWM channel 1
ETRIG1
PWM channel 3
Consult the ATD section for information about the analog-to-digital converter module. References to
freeze mode are equivalent to active BDM mode.
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Device Overview MC9S12P-Family
1.14
S12CPMU Configuration
The bandgap reference voltage VBG and the output voltage of the temperature sensor VHT can be
connected to the ATD channel SPECIAL17 (see Table 9-15.) using the VSEL (Voltage Access Select Bit)
in CPMUHTCTL register (see Table 7-13.)
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Chapter 2 Port Integration Module (S12PPIMV1)
Revision History
Rev. No.
Date
(Item No.) (Submitted By)
Sections
Affected
Substantial Change(s)
V01.00
19 Mar 2008
Initial version
V01.01
05 May 2008
Corrected mistakes in Port J register and field names
V01.02
12 Jan 2009
Corrected PERxAD register descriptions
Replaced VREG_API with API_EXTCLK
Minor corrections
2.1
2.1.1
Introduction
Overview
The S12P Family Port Integration Module establishes the interface between the peripheral modules and
the I/O pins for all ports. It controls the electrical pin properties as well as the signal prioritization and
multiplexing on shared pins.
This section covers:
• Port A and B used as general purpose I/O
• Port E associated with the IRQ, XIRQ interrupt inputs
• Port T associated with 1 timer module
• Port S associated with 1 SCI module
• Port M associated with 1 MSCAN and 1 SPI module
• Port P connected to the PWM - inputs can be used as an external interrupt source
• Port J used as general purpose I/O - inputs can be used as an external interrupt source
• Port AD associated with one 10-channel ATD module
Most I/O pins can be configured by register bits to select data direction and drive strength, to enable and
select pull-up or pull-down devices.
NOTE
This section assumes the availability of all features (80-pin package option).
Some functions are not available on lower pin count package options. Refer
to the pin-out summary section.
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Port Integration Module (S12PPIMV1)
2.1.2
Features
The Port Integration Module includes these distinctive registers:
• Data registers and data direction registers for Ports A, B, E, T, S, M, P, J and AD when used as
general purpose I/O
• Control registers to enable/disable pull devices and select pull-ups/pull-downs on Ports T, S, M, P
and J on per-pin basis
• Control registers to enable/disable pull-up devices on Port AD on per-pin basis
• Single control register to enable/disable pull-ups on Ports A, B, and E, on per-port basis and on
BKGD pin
• Control registers to enable/disable reduced output drive on Ports T, S, M, P, J and AD on per-pin
basis
• Single control register to enable/disable reduced output drive on Ports A, B, and E on per-port basis
• Control registers to enable/disable open-drain (wired-or) mode on Ports S and M
• Interrupt flag register for pin interrupts on Ports P and J
• Control register to configure IRQ pin operation
• Routing register to support module port relocation
• Free-running clock outputs
A standard port pin has the following minimum features:
• Input/output selection
• 5V output drive with two selectable drive strengths
• 5V digital and analog input
• Input with selectable pull-up or pull-down device
Optional features supported on dedicated pins:
•
Open drain for wired-or connections
•
Interrupt inputs with glitch filtering
2.2
External Signal Description
This section lists and describes the signals that do connect off-chip.
Table 2-1 shows all the pins and their functions that are controlled by the Port Integration Module.
NOTE
If there is more than one function associated with a pin, the priority is
indicated by the position in the table from top (highest priority) to bottom
(lowest priority).
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Port Integration Module (S12PPIMV1)
Table 2-1. Pin Functions and Priorities
Port
Pin Name
Pin Function
& Priority(1)
I/O
-
BKGD
MODC (2)
I
BKGD
I/O S12X_BDM communication pin
A
PA[7:0]
GPIO
I/O General purpose
GPIO
B
PB[7:0]
GPIO
I/O General purpose
GPIO
E
PE[7]
ECLKX2
O
GPIO
Free-running clock at core clock rate (ECLK x 2)
GPIO
I/O General purpose
GPIO
I/O General purpose
PE[4]
ECLK
O
GPIO
I/O General purpose
GPIO
I/O General purpose
PE[1]
IRQ
I
Maskable level- or falling edge-sensitive interrupt
GPI
I
General purpose
PT[7:6]
XIRQ
I
Non-maskable level-sensitive interrupt
GPI
I
General purpose
IOC[7:6]
I/O Timer Channels 7 - 6
GPIO
I/O General purpose
IOC5
I/O Timer Channel 5
(PWM5)
O
Pulse Width Modulator channel 5
API_EXTCLK
O
VREG Autonomous Periodical Interrupt Clock
PT4
GPIO
I/O General purpose
IOC4
I/O Timer Channel 4
(PWM4)
GPIO
PT[3:1]
PT0
IOC[3:1]
O
I/O Timer Channels 3 - 1
I/O General purpose
IOC0
I/O Timer Channel 0
O
Pulse Width Modulator channel 0
I/O General purpose
PS[3:2]
GPIO
I/O General purpose
PS1
TXD
O
GPIO
I/O General purpose
RXD
GPIO
GPIO
I/O General purpose
GPIO
PS0
BKGD
Pulse Width Modulator channel 4
GPIO
(PWM0)
Pin Function
after Reset
Free-running clock at bus clock rate or programmable downscaled bus clock
PE[3:2]
PT5
S
MODC input during RESET
PE[6:5]
PE[0]
T
Description
I
GPIO
Serial Communication Interface transmit pin
Serial Communication Interface receive pin
I/O General purpose
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Port Integration Module (S12PPIMV1)
Port
Pin Name
Pin Function
& Priority(1)
M
PM5
SCK
I/O Serial Peripheral Interface serial clock pin
GPIO
I/O General purpose
MOSI
I/O Serial Peripheral Interface master out/slave in pin
PM4
GPIO
PM3
SS
GPIO
PM2
PM1
I/O General purpose
I/O Serial Peripheral Interface slave select output in master mode,
input in slave mode or master mode.
I/O General purpose
I/O Serial Peripheral Interface master in/slave out pin
I/O General purpose
TXCAN
RXCAN
PP7
GPIO/KWP7
PP5
PWM5
GPIO/KWP5
PP[4:0]
GPIO
GPIO
GPIO
P
Pin Function
after Reset
Description
MISO
GPIO
PM0
I/O
PWM[4:0]
O
MSCAN transmit pin
I/O General purpose
I
MSCAN receive
I/O General purpose
I/O General purpose; with interrupt
I/O Pulse Width Modulator channel 5; emergency shut-down
I/O General purpose; with interrupt
O
Pulse Width Modulator channel 4 - 0
GPIO/KWP[4:0]
I/O General purpose; with interrupt
I/O General purpose; with interrupt
J
PJ[7:6]
GPIO/KWJ[7:6]
PJ[2:0]
GPIO/KWJ[2:0]
AD
PAD[9:0]
GPIO
GPIO
GPIO
I/O General purpose; with interrupt
I/O General purpose
GPIO
AN[9:0]
I ATD analog
1. Signals in brackets denote alternative module routing pins.
2. Function active when RESET asserted.
2.3
Memory Map and Register Definition
This section provides a detailed description of all Port Integration Module registers.
2.3.1
Memory Map
Table 2-2 shows the register map of the Port Integration Module.
Table 2-2. Block Memory Map
Port
A
B
Offset or
Address
Register
Access
Reset Value
Section/Page
0x0000
PORTA—Port A Data Register
R/W
0x00
2.3.3/2-63
0x0001
PORTB—Port B Data Register
R/W
0x00
2.3.4/2-63
0x0002
DDRA—Port A Data Direction Register
R/W
0x00
2.3.5/2-64
0x0003
DDRB—Port B Data Direction Register
R/W
0x00
2.3.6/2-64
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52
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
Table 2-2. Block Memory Map (continued)
Port
E
A
B
E
E
T
Offset or
Address
Register
Access
Reset Value
Section/Page
R
0x00
2.3.7/2-65
0x0004
:
0x0007
PIM Reserved
0x0008
PORTE—Port E Data Register
R/W(1)
0x00
2.3.8/2-65
0x0009
DDRE—Port E Data Direction Register
R/W1
0x00
2.3.9/2-66
-
-
-
(2)
0x000A
:
0x000B
Non-PIM address range
0x000C
PUCR—Pull-up Up Control Register
R/W1
0x50
2.3.10/2-67
0x000D
RDRIV—Reduced Drive Register
R/W1
0x00
2.3.11/2-68
0x000E
:
0x001B
Non-PIM address range2
-
-
-
0x001C
ECLKCTL—ECLK Control Register
R/W1
0xC0 / 0x80(3)
2.3.12/2-69
0x001D
PIM Reserved
R
0x00
2.3.13/2-69
R/W1
0x40
2.3.14/2-70
R
0x00
2.3.15/2-70
-
-
-
0x001E
IRQCR—IRQ Control Register
0x001F
PIM Reserved
range2
0x0020
:
0x023F
Non-PIM address
0x0240
PTT—Port T Data Register
R/W
0x00
2.3.16/2-71
0x0241
PTIT—Port T Input Register
R
(4)
2.3.17/2-72
0x0242
DDRT—Port T Data Direction Register
R/W
0x00
2.3.18/2-73
0x0243
RDRT—Port T Reduced Drive Register
R/W
0x00
2.3.19/2-74
0x0244
PERT—Port T Pull Device Enable Register
R/W
0x00
2.3.20/2-74
0x0245
PPST—Port T Polarity Select Register
R/W
0x00
2.3.21/2-75
0x0246
PIM Reserved
R
0x00
2.3.22/2-75
0x0247
Port T Routing Register
R/W
0x00
2.3.23/2-76
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Freescale Semiconductor
53
Port Integration Module (S12PPIMV1)
Table 2-2. Block Memory Map (continued)
Port
Offset or
Address
S
0x0248
M
P
Register
Access
Reset Value
Section/Page
PTS—Port S Data Register
R/W
0x00
2.3.24/2-77
0x0249
PTIS—Port S Input Register
R
4
2.3.25/2-77
0x024A
DDRS—Port S Data Direction Register
R/W
0x00
2.3.26/2-78
0x024B
RDRS—Port S Reduced Drive Register
R/W
0x00
2.3.27/2-79
0x024C
PERS—Port S Pull Device Enable Register
R/W
0xFF
2.3.28/2-79
0x024D
PTPS—Port S Polarity Select Register
R/W
0x00
2.3.29/2-80
0x024E
WOMS—Port S Wired-Or Mode Register
R/W
0x00
2.3.30/2-80
0x024F
PIM Reserved
R
0x00
2.3.39/2-86
0x0250
PTM—Port M Data Register
R/W
0x00
2.3.32/2-81
0x0251
PTIM—Port M Input Register
R
4
2.3.33/2-82
0x0252
DDRM—Port M Data Direction Register
R/W
0x00
2.3.34/2-83
0x0253
RDRM—Port M Reduced Drive Register
R/W
0x00
2.3.35/2-84
0x0254
PERM—Port M Pull Device Enable Register
R/W
0x00
2.3.36/2-85
0x0255
PPSM—Port M Polarity Select Register
R/W
0x00
2.3.37/2-85
0x0256
WOMM—Port M Wired-Or Mode Register
R/W
0x00
2.3.38/2-86
0x0257
PIM Reserved
R
0x00
2.3.39/2-86
0x0258
PTP—Port P Data Register
R/W
0x00
2.3.40/2-87
0x0259
PTIP—Port P Input Register
R
4
2.3.41/2-88
0x025A
DDRP—Port P Data Direction Register
R/W
0x00
2.3.42/2-88
0x025B
RDRP—Port P Reduced Drive Register
R/W
0x00
2.3.43/2-89
0x025C
PERP—Port P Pull Device Enable Register
R/W
0x00
2.3.44/2-90
0x025D
PTPP—Port P Polarity Select Register
R/W
0x00
2.3.45/2-90
0x025E
PIEP—Port P Interrupt Enable Register
R/W
0x00
2.3.46/2-91
0x025F
PIFP—Port P Interrupt Flag Register
R/W
0x00
2.3.47/2-91
0x0260
:
0x0267
PIM Reserved
R
0x00
2.3.48/2-92
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
Table 2-2. Block Memory Map (continued)
Port
Offset or
Address
J
0x0268
AD
Register
Access
Reset Value
Section/Page
PTJ—Port J Data Register
R/W
0x00
2.3.49/2-92
0x0269
PTIJ—Port J Input Register
R
4
2.3.50/2-93
0x026A
DDRJ—Port J Data Direction Register
R/W
0x00
2.3.51/2-93
0x026B
RDRJ—Port J Reduced Drive Register
R/W
0x00
2.3.52/2-94
0x026C
PERJ—Port J Pull Device Enable Register
R/W
0xFF
2.3.53/2-94
0x026D
PPSJ—Port J Polarity Select Register
R/W
0x00
2.3.54/2-95
0x026E
PIEJ—Port J Interrupt Enable Register
R/W
0x00
2.3.55/2-95
0x026F
PIFJ—Port J Interrupt Flag Register
R/W
0x00
2.3.56/2-96
0x0270
PT0AD—Port AD Data Register
R
0x00
2.3.57/2-96
0x0271
PT1AD—Port AD Data Register
R/W
0x00
2.3.58/2-97
0x0272
DDR0AD—Port AD Data Direction Register
R
0x00
2.3.59/2-97
0x0273
DDR1AD—Port AD Data Direction Register
R/W
0x00
2.3.60/2-98
0x0274
RDR0AD—Port AD Reduced Drive Register
R
0x00
2.3.61/2-98
0x0275
RDR1AD—Port AD Reduced Drive Register
R/W
0x00
2.3.62/2-99
0x0276
PER0AD—Port AD Pull Up Enable Register
R
0x00
2.3.62/2-99
0x0277
PER1AD—Port AD Pull Up Enable Register
R/W
0x00
2.3.64/2-100
R
0x00
2.3.65/2-100
0x0278 PIM Reserved
:
0x027F
1. Write access not applicable for one or more register bits. Refer to register description.
2. Refer to device memory map to determine related module.
3. Mode dependent.
4. Read always returns logic level on pins.
Register
Name
0x0000
PORTA
0x0001
PORTB
R
W
R
W
0x0002
DDRA
R
W
0x0003
DDRB
W
R
Bit 7
6
5
4
3
2
1
Bit 0
PA7
PA6
PA5
PA4
PA3
PA2
PA1
PA0
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
DDRA7
DDRA6
DDRA5
DDRA4
DDRA3
DDRA2
DDRA1
DDRA0
DDRB7
DDRB6
DDRB5
DDRB4
DDRB3
DDRB2
DDRB1
DDRB0
= Unimplemented or Reserved
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Freescale Semiconductor
55
Port Integration Module (S12PPIMV1)
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
0x0004
R
Reserved W
0
0
0
0
0
0
0
0
0x0005
R
Reserved W
0
0
0
0
0
0
0
0
0x0006
R
Reserved W
0
0
0
0
0
0
0
0
0x0007
R
Reserved W
0
0
0
0
0
0
0
0
PE7
PE6
PE5
PE4
PE3
PE2
PE1
PE0
DDRE7
DDRE6
DDRE5
DDRE4
DDRE3
DDRE2
0
0
PUPBE
PUPAE
RDPB
RDPA
0x0008
PORTE
0x0009
DDRE
R
W
R
W
0x000A R
0x000B W
Non-PIM
Address
Range
0x000C
PUCR
0x000D
RDRIV
R
Non-PIM Address Range
0
W
R
0
BKPUE
0
0
0
RDPE
W
0x000E– R
0x001B W
Non-PIM
Address
Range
0x001C R
ECLKCTL W
0x001D R
Reserved W
0x001E
IRQCR
PUPEE
R
W
0x001F
R
Reserved W
0
0
0
0
Non-PIM Address Range
NECLK
NCLKX2
DIV16
EDIV4
EDIV3
EDIV2
EDIV1
EDIV0
0
0
0
0
0
0
0
0
IRQE
IRQEN
0
0
0
0
0
0
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
Register
Name
Bit 7
6
5
0x0020– R
0x023F W
Non-PIM
Address
Range
0x0240
PTT
R
W
0x0241
PTIT
W
0x0242
DDRT
W
0x0243
RDRT
0x0244
PERT
0x0245
PPST
R
R
R
W
R
W
R
W
0x0246
R
Reserved W
0x0247
PTTRR
R
W
0x0249
PTIS
W
0x024A
DDRS
R
R
R
W
0x024C
PERS
W
0x024D
PPSS
R
R
R
2
1
Bit 0
PTT7
PTT6
PTT5
PTT4
PTT3
PTT2
PTT1
PTT0
PTIT7
PTIT6
PTIT5
PTIT4
PTIT3
PTIT2
PTIT1
PTIT0
DDRT7
DDRT6
DDRT5
DDRT4
DDRT3
DDRT2
DDRT1
DDRT0
RDRT7
RDRT6
RDRT5
RDRT4
RDRT3
RDRT2
RDRT1
RDRT0
PERT7
PERT6
PERT5
PERT4
PERT3
PERT2
PERT1
PERT0
PPST7
PPST6
PPST5
PPST4
PPST3
PPST2
PPST1
PPST0
0
0
0
0
0
0
0
0
0
0
PTTRR5
PTTRR4
0
0
0
0
0
0
0
PTS3
PTS2
PTS1
PTS0
0
0
0
0
PTIS3
PTIS2
PTIS1
PTIS0
0
0
0
0
DDRS3
DDRS2
DDRS1
DDRS0
0
0
0
0
RDRS3
RDRS2
RDRS1
RDRS0
0
0
0
0
PERS3
PERS2
PERS1
PERS0
0
0
0
0
PPSS3
PPSS2
PPSS1
PPSS0
W
0x024B
RDRS
3
Non-PIM Address Range
W
0x0248
PTS
4
W
PTTRR0
= Unimplemented or Reserved
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Freescale Semiconductor
57
Port Integration Module (S12PPIMV1)
Register
Name
0x024E
WOMS
R
R
W
0x0252
DDRM
W
0x0254
PERM
0x0255
PPSM
0x0256
WOMM
R
R
R
R
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
R
W
R
W
0x0258
PTP
W
0x0259
PTIP
W
R
R
R
W
0x025B
RDRP
W
0x025C
PERP
W
0x025D
PPSP
4
W
0x0257
R
Reserved W
0x025A
DDRP
5
W
0x0251
PTIM
0x0253
RDRM
6
3
2
1
Bit 0
WOMS3
WOMS2
WOMS1
WOMS0
0
0
0
0
0
PTM5
PTM4
PTM3
PTM2
PTM1
PTM0
PTIM5
PTIM4
PTIM3
PTIM2
PTIM1
PTIM0
DDRM5
DDRM4
DDRM3
DDRM2
DDRM1
DDRM0
RDRM5
RDRM4
RDRM3
RDRM2
RDRM1
RDRM0
PERM5
PERM4
PERM3
PERM2
PERM1
PERM0
PPSM5
PPSM4
PPSM3
PPSM2
PPSM1
PPSM0
WOMM5
WOMM4
WOMM3
WOMM2
WOMM1
WOMM0
0
0
0
0
0
0
PTP5
PTP4
PTP3
PTP2
PTP1
PTP0
PTIP5
PTIP4
PTIP3
PTIP2
PTIP1
PTIP0
DDRP5
DDRP4
DDRP3
DDRP2
DDRP1
DDRP0
RDRP5
RDRP4
RDRP3
RDRP2
RDRP1
RDRP0
PERP5
PERP4
PERP3
PERP2
PERP1
PERP0
PPSP5
PPSP4
PPSP3
PPSP2
PPSP1
PPSP0
W
0x024F
R
Reserved W
0x0250
PTM
Bit 7
R
R
R
W
PTP7
PTIP7
DDRP7
RDRP7
PERP7
PPSP7
0
0
0
0
0
0
= Unimplemented or Reserved
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58
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
Register
Name
0x025E
PIEP
0x025F
PIFP
Bit 7
R
W
R
W
PIEP7
PIFP7
6
0
0
5
4
3
2
1
Bit 0
PIEP5
PIEP4
PIEP3
PIEP2
PIEP1
PIEP0
PIFP5
PIFP4
PIFP3
PIFP2
PIFP1
PIFP0
0x0260
R
Reserved W
0
0
0
0
0
0
0
0
0x0261
R
Reserved W
0
0
0
0
0
0
0
0
0x0262
R
Reserved W
0
0
0
0
0
0
0
0
0x0263
R
Reserved W
0
0
0
0
0
0
0
0
0x0264
R
Reserved W
0
0
0
0
0
0
0
0
0x0265
R
Reserved W
0
0
0
0
0
0
0
0
0x0266
R
Reserved W
0
0
0
0
0
0
0
0
0x0267
R
Reserved W
0
0
0
0
0
0
0
0
PTJ7
PTJ6
0
0
0
PTJ2
PTJ1
PTJ0
PTIJ7
PTIJ6
0
0
0
PTIJ2
PTIJ1
PTIJ0
DDRJ7
DDRJ6
0
0
0
DDRJ2
DDRJ1
DDRJ0
RDRJ7
RDRJ6
0
0
0
RDRJ2
RDRJ1
RDRJ0
PERJ7
PERJ6
0
0
0
PERJ2
PERJ1
PERJ0
0x0268
PTJ
0x0269
PTIJ
0x026A
DDRJ
0x026B
RDRJ
0x026C
PERJ
R
W
R
W
R
W
R
W
R
W
= Unimplemented or Reserved
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59
Port Integration Module (S12PPIMV1)
Register
Name
0x026D
PPSJ
0x026E
PIEJ
0x026F
PIFJ
0x0270
PT0AD
0x0271
PT1AD
R
W
R
W
R
W
R
Bit 7
6
5
4
3
PPSJ7
PPSJ6
PIEJ7
PIEJ6
PIFJ7
PIFJ6
0
2
1
Bit 0
0
0
0
PPSJ2
PPSJ1
PPSJ0
0
0
0
PIEJ2
PIEJ1
PIEJ0
0
0
0
PIFJ2
PIFJ1
PIFJ0
0
0
0
0
0
PT0AD1
PT0AD0
PT1AD7
PT1AD6
PT1AD5
PT1AD4
PT1AD3
PT1AD2
PT1AD1
PT1AD0
0
0
0
0
0
0
DDR0AD1
DDR0AD0
DDR1AD6
DDR1AD5
DDR1AD4
DDR1AD3
DDR1AD2
DDR1AD1
DDR1AD0
0
0
0
0
0
RDR0AD1
RDR0AD0
RDR1AD6
RDR1AD5
RDR1AD4
RDR1AD3
RDR1AD2
RDR1AD1
RDR1AD0
0
0
0
0
0
PER0AD1
PER0AD0
PER1AD6
PER1AD5
PER1AD4
PER1AD3
PER1AD2
PER1AD1
PER1AD0
W
R
W
0x0272
R
DDR0AD W
0x0273
R
DDR1AD W DDR1AD7
0x0274
R
RDR0AD W
0
0x0275
R
RDR1AD W RDR1AD7
0x0276
R
PER0AD W
0
0x0277
R
PER1AD W PER1AD7
0x0278
R
Reserved W
0
0
0
0
0
0
0
0
0x0279
R
Reserved W
0
0
0
0
0
0
0
0
0x027A R
Reserved W
0
0
0
0
0
0
0
0
0x027B R
Reserved W
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
0x027C R
Reserved W
0
0
0
0
0
0
0
0
0x027D R
Reserved W
0
0
0
0
0
0
0
0
0x027E R
Reserved W
0
0
0
0
0
0
0
0
0x027F
R
Reserved W
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
2.3.2
Register Descriptions
The following table summarizes the effect of the various configuration bits, i.e. data direction (DDR),
output level (IO), reduced drive (RDR), pull enable (PE), pull select (PS) on the pin function and pull
device activity.
The configuration bit PS is used for two purposes:
1. Configure the sensitive interrupt edge (rising or falling), if interrupt is enabled.
2. Select either a pull-up or pull-down device if PE is active.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
61
Port Integration Module (S12PPIMV1)
Table 2-3. Pin Configuration Summary
DDR
IO
RDR
PE
PS(1)
IE(2)
0
x
x
0
x
0
Input
Disabled
Disabled
0
x
x
1
0
0
Input
Pull Up
Disabled
0
x
x
1
1
0
Input
Pull Down
Disabled
0
x
x
0
0
1
Input
Disabled
Falling edge
0
x
x
0
1
1
Input
Disabled
Rising edge
0
x
x
1
0
1
Input
Pull Up
Falling edge
0
x
x
1
1
1
Input
Pull Down
Rising edge
1
0
0
x
x
0
Output, full drive to 0
Disabled
Disabled
1
1
0
x
x
0
Output, full drive to 1
Disabled
Disabled
1
0
1
x
x
0
Output, reduced drive to 0
Disabled
Disabled
1
1
1
x
x
0
Output, reduced drive to 1
Disabled
Disabled
1
0
0
x
0
1
Output, full drive to 0
Disabled
Falling edge
1
1
0
x
1
1
Output, full drive to 1
Disabled
Rising edge
1
0
1
x
0
1
Output, reduced drive to 0
Disabled
Falling edge
1
1
Output, reduced drive to 1
Disabled
Rising edge
1
1
1
x
1. Always “0” on Port A, B, E, and AD.
2. Applicable only on Port P and J.
Function
Pull Device
Interrupt
NOTE
All register bits in this module are completely synchronous to internal
clocks during a register read.
NOTE
Figure of port data registers also display the alternative functions if
applicable on the related pin as defined in Table 2-1. Names in brackets
denote the availability of the function when using a specific routing option.
NOTE
Figures of module routing registers also display the module instance or
module channel associated with the related routing bit.
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.3
Port A Data Register (PORTA)
Access: User read/write(1)
Address 0x0000
7
6
5
4
3
2
1
0
PA7
PA6
PA5
PA4
PA3
PA2
PA1
PA0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-1. Port A Data Register (PORTA)
1. Read: Anytime. The data source is depending on the data direction value.
Write: Anytime
Table 2-4. PORTA Register Field Descriptions
Field
Description
7-0
PA
Port A general purpose input/output data—Data Register
The associated pin can be used as general purpose I/O. In general purpose output mode the register bit value is
driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
2.3.4
Port B Data Register (PORTB)
Access: User read/write(1)
Address 0x0001
7
6
5
4
3
2
1
0
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-2. Port B Data Register (PORTB)
1. Read: Anytime. The data source is depending on the data direction value.
Write: Anytime
Table 2-5. PORTB Register Field Descriptions
Field
Description
7-0
PB
Port B general purpose input/output data—Data Register
The associated pin can be used as general purpose I/O. In general purpose output mode the register bit value is
driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
63
Port Integration Module (S12PPIMV1)
2.3.5
Port A Data Direction Register (DDRA)
Access: User read/write(1)
Address 0x0002
7
6
5
4
3
2
1
0
DDRA7
DDRA6
DDRA5
DDRA4
DDRA3
DDRA2
DDRA1
DDRA0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-3. Port A Data Direction Register (DDRA)
1. Read: Anytime
Write: Anytime
Table 2-6. DDRA Register Field Descriptions
Field
7-0
DDRA
Description
Port A Data Direction—
This bit determines whether the associated pin is an input or output.
1 Associated pin is configured as output
0 Associated pin is configured as input
2.3.6
Port B Data Direction Register (DDRB)
Access: User read/write(1)
Address 0x0003
7
6
5
4
3
2
1
0
DDRB7
DDRB6
DDRB5
DDRB4
DDRB3
DDRB2
DDRB1
DDRB0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-4. Port B Data Direction Register (DDRB)
1. Read: Anytime
Write: Anytime
Table 2-7. DDRB Register Field Descriptions
Field
7-0
DDRB
Description
Port B Data Direction—
This bit determines whether the associated pin is an input or output.
1 Associated pin is configured as output
0 Associated pin is configured as input
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64
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.7
PIM Reserved Register
Access: User read(1)
Address 0x0004 to 0x0007
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 2-5. PIM Reserved Register
1. Read: Always reads 0x00
Write: Unimplemented
2.3.8
Port E Data Register (PORTE)
Access: User read/write(1)
Address 0x0008
7
6
5
4
3
2
1
0
PE7
PE6
PE5
PE4
PE3
PE2
PE1
PE0
ECLKX2
—
—
ECLK
—
—
IRQ
XIRQ
0
0
0
0
0
0
—(2)
—2
R
W
Altern.
Function
Reset
= Unimplemented or Reserved
Figure 2-6. Port E Data Register (PORTE)
1. Read: Anytime. The data source is depending on the data direction value.
Write: Anytime
2. These registers are reset to zero. Two bus clock cycles after reset release the register values are updated with the associated
pin values.
Table 2-8. PORTE Register Field Descriptions
Field
Description
7
PE
Port E general purpose input/output data—Data Register, ECLKX2 output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The ECLKX2 output function takes precedence over the general purpose I/O function if enabled.
6-5, 3-2
PE
Port E general purpose input/output data—Data Register
The associated pin can be used as general purpose I/O. In general purpose output mode the register bit value is
driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
65
Port Integration Module (S12PPIMV1)
Table 2-8. PORTE Register Field Descriptions (continued)
Field
Description
4
PE
Port E general purpose input/output data—Data Register, ECLK output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The ECLK output function takes precedence over the general purpose I/O function if enabled.
1
PE
Port E general purpose input data and interrupt—Data Register, IRQ input.
This pin can be used as general purpose and IRQ input.
0
PE
Port E general purpose input data and interrupt—Data Register, XIRQ input.
This pin can be used as general purpose and XIRQ input.
2.3.9
Port E Data Direction Register (DDRE)
Access: User read/write(1)
Address 0x0009
7
6
5
4
3
2
DDRE7
DDRE6
DDRE5
DDRE4
DDRE3
DDRE2
0
0
0
0
0
0
R
1
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 2-7. Port E Data Direction Register (DDRE)
1. Read: Anytime
Write: Anytime
Table 2-9. DDRE Register Field Descriptions
Field
7-2
DDRE
Description
Port E Data Direction—
This bit determines whether the associated pin is an input or output.
1 Associated pin is configured as output
0 Associated pin is configured as input
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66
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.10
Ports A, B, E, BKGD pin Pull-up Control Register (PUCR)
Access: User read/write(1)
Address 0x000C
7
R
6
5
0
4
0
BKPUE
3
2
0
0
PUPEE
1
0
PUPBE
PUPAE
0
0
W
Reset
0
1
0
1
0
0
= Unimplemented or Reserved
Figure 2-8. Ports ABEK, BKGD pin Pull-up Control Register (PUCR)
1. Read:Anytime in single-chip modes.
Write:Anytime, except BKPUE which is writable in Special Single-Chip Mode only.
Table 2-10. PUCR Register Field Descriptions
Field
Description
6
BKPUE
BKGD pin pull-up Enable—Enable pull-up device on pin
This bit configures whether a pull-up device is activated, if the pin is used as input. If a pin is used as output this bit
has no effect.
1 Pull-up device enabled
0 Pull-up device disabled
4
PUPEE
Port E Pull-up Enable—Enable pull-up devices on all port input pins except pins 5 and 6
This bit configures whether a pull-up device is activated on all associated port input pins. If a pin is used as output
this bit has no effect.
Pins 5 and 6 have pull-down devices enabled only during reset. This bit has no effect on these pins.
1 Pull-up device enabled
0 Pull-up device disabled
1
PUPBE
Port B Pull-up Enable—Enable pull-up devices on all port input pins
This bit configures whether a pull-up device is activated on all associated port input pins. If a pin is used as output
this bit has no effect.
1 Pull-up device enabled
0 Pull-up device disabled
0
PUPAE
Port A Pull-up Enable—Enable pull-up devices on all port input pins
This bit configures whether a pull-up device is activated on all associated port input pins. If a pin is used as output
this bit has no effect.
1 Pull-up device enabled
0 Pull-up device disabled
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Freescale Semiconductor
67
Port Integration Module (S12PPIMV1)
2.3.11
Ports A, B, E Reduced Drive Register (RDRIV)
Access: User read/write(1)
Address 0x000D
R
7
6
5
0
0
0
4
3
2
0
0
RDPE
1
0
RDPB
RDPA
0
0
W
Reset
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 2-9. Ports ABEK Reduced Drive Register (RDRIV)
1. Read: Anytime
Write: Anytime
Table 2-11. RDRIV Register Field Descriptions
Field
Description
4
RDPE
Port E reduced drive—Select reduced drive for output port
This bit configures the drive strength of all associated port output pins as either full or reduced. If a pin is used as
input this bit has no effect. The reduced drive function is independent of which function is being used on a particular
pin.
1 Reduced drive selected (approx. 1/5 of the full drive strength)
0 Full drive strength enabled
1
RDPE
Port B reduced drive—Select reduced drive for output port
This bit configures the drive strength of all associated port output pins as either full or reduced. If a pin is used as
input this bit has no effect. The reduced drive function is independent of which function is being used on a particular
pin.
1 Reduced drive selected (approx. 1/5 of the full drive strength)
0 Full drive strength enabled
0
RDPA
Port A reduced drive—Select reduced drive for output port
This bit configures the drive strength of all associated port output pins as either full or reduced. If a pin is used as
input this bit has no effect. The reduced drive function is independent of which function is being used on a particular
pin.
1 Reduced drive selected (approx. 1/5 of the full drive strength)
0 Full drive strength enabled
S12P-Family Reference Manual, Rev. 1.13
68
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.12
ECLK Control Register (ECLKCTL)
Access: User read/write(1)
Address 0x001C
7
6
5
4
3
2
1
0
NECLK
NCLKX2
DIV16
EDIV4
EDIV3
EDIV2
EDIV1
EDIV0
Reset:
Mode
Dependent
1
0
0
0
0
0
0
Special
single-chip
0
1
0
0
0
0
0
0
Normal
single-chip
1
1
0
0
0
0
0
0
R
W
= Unimplemented or Reserved
Figure 2-10. ECLK Control Register (ECLKCTL)
1. Read: Anytime
Write: Anytime
Table 2-12. ECLKCTL Register Field Descriptions
Field
Description
7
NECLK
No ECLK—Disable ECLK output
This bit controls the availability of a free-running clock on the ECLK pin. This clock has a fixed rate of equivalent to
the internal bus clock.
1 ECLK disabled
0 ECLK enabled
6
NCLKX2
No ECLKX2—Disable ECLKX2 output
This bit controls the availability of a free-running clock on the ECLKX2 pin. This clock has a fixed rate of twice the
internal bus clock.
1 ECLKX2 disabled
0 ECLKX2 enabled
5
DIV16
Free-running ECLK pre-divider—Divide by 16
This bit enables a divide-by-16 stage on the selected EDIV rate.
1 Divider enabled: ECLK rate = EDIV rate divided by 16
0 Divider disabled: ECLK rate = EDIV rate
4-0
EDIV
Free-running ECLK Divider—Configure ECLK rate
These bits determine the rate of the free-running clock on the ECLK pin.
00000 ECLK rate = bus clock rate
00001 ECLK rate = bus clock rate divided by 2
00010 ECLK rate = bus clock rate divided by 3,...
11111 ECLK rate = bus clock rate divided by 32
2.3.13
PIM Reserved Register
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
69
Port Integration Module (S12PPIMV1)
Access: User read(1)
Address 0x001D
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 2-11. PIM Reserved Register
1. Read: Always reads 0x00
Write: Unimplemented
2.3.14
IRQ Control Register (IRQCR)
Access: User read/write(1)
Address 0x001E
7
6
IRQE
IRQEN
0
1
R
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 2-12. IRQ Control Register (IRQCR)
1. Read: See individual bit descriptions below.
Write: See individual bit descriptions below.
Table 2-13. IRQCR Register Field Descriptions
Field
7
IRQE
Description
IRQ select edge sensitive only—
Special mode: Read or write anytime.
Normal mode: Read anytime, write once.
1 IRQ pin configured to respond only to falling edges. Falling edges on the IRQ pin will be detected anytime IRQE=1
and will be cleared only upon a reset or the servicing of the IRQ interrupt.
0 IRQ pin configured for low level recognition
6
IRQEN
IRQ enable—
Read or write anytime.
1 IRQ pin is connected to interrupt logic
0 IRQ pin is disconnected from interrupt logic
2.3.15
PIM Reserved Register
This register is reserved for factory testing of the PIM module and is not available in normal operation.
Writing to this register when in special modes can alter the pin functionality.
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70
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
Access: User read(1)
Address 0x001F
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 2-13. PIM Reserved Register
1. Read: Always reads 0x00
Write: Unimplemented
2.3.16
Port T Data Register (PTT)
Access: User read/write(1)
Address 0x0240
7
6
5
4
3
2
1
0
PTT7
PTT6
PTT5
PTT4
PTT3
PTT2
PTT1
PTT0
IOC7
IOC6
IOC5
IOC4
IOC3
IOC2
IOC1
IOC0
—
—
(PWM5)
(PWM4)
—
—
—
(PWM0)
—
—
API_EXTCLK
—
—
—
—
—
0
0
0
0
0
0
0
0
R
W
Altern.
Function
Reset
Figure 2-14. Port T Data Register (PTT)
1. Read: Anytime. The data source is depending on the data direction value.
Write: Anytime
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
71
Port Integration Module (S12PPIMV1)
Table 2-14. PTT Register Field Descriptions
Field
Description
7-6, 3-1
PTT
Port T general purpose input/output data—Data Register, TIM output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The TIM output function takes precedence over the general purpose I/O function if the related channel is enabled.
5
PTT
Port T general purpose input/output data—Data Register, TIM output, routed PWM output, API_EXTCLK output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The TIM output function takes precedence over the routed PWM, API_EXTCLK function and the general purpose
I/O function if the related channel is enabled.
• The routed PWM function takes precedence over API_EXTCLK and the general purpose I/O function if the related
channel is enabled.
• The API_EXTCLK takes precedence over the general purpose I/O function if enabled.
4,0
PTT
Port T general purpose input/output data—Data Register, TIM output, routed PWM output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The TIM output function takes precedence over the routed PWM and the general purpose I/O function if the
related channel is enabled.
• The routed PWM function takes precedence over the general purpose I/O function if the related channel is
enabled.
2.3.17
Port T Input Register (PTIT)
Access: User read(1)
Address 0x0241
R
7
6
5
4
3
2
1
0
PTIT7
PTIT6
PTIT5
PTIT4
PTIT3
PTIT2
PTIT1
PTIT0
u
u
u
u
u
u
u
u
W
Reset
= Unimplemented or Reserved
u = Unaffected by reset
Figure 2-15. Port T Input Register (PTIT)
1. Read: Anytime
Write:Never, writes to this register have no effect.
S12P-Family Reference Manual, Rev. 1.13
72
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
Table 2-15. PTIT Register Field Descriptions
Field
Description
7-0
PTIT
Port T input data—
A read always returns the buffered input state of the associated pin. It can be used to detect overload or short circuit
conditions on output pins.
2.3.18
Port T Data Direction Register (DDRT)
Access: User read/write(1)
Address 0x0242
7
6
5
4
3
2
1
0
DDRT7
DDRT6
DDRT5
DDRT4
DDRT3
DDRT2
DDRT1
DDRT0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-16. Port T Data Direction Register (DDRT)
1. Read: Anytime
Write: Anytime
Table 2-16. DDRT Register Field Descriptions
Field
Description
7-6, 3-1
DDRT
Port T data direction—
This bit determines whether the pin is an input or output.
The TIM forces the I/O state to be an output for a timer port associated with an enabled output compare. In this case
the data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
5
DDRT
Port T data direction—
This bit determines whether the pin is an input or output.
The TIM forces the I/O state to be an output for a timer port associated with an enabled output compare. Else the
routed PWM forces the I/O state to be an output for an enabled channel. Else the API_EXTCLK forces the I/O state
to be an output if enabled. In these cases the data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
4,0
DDRT
Port T data direction—
This bit determines whether the pin is an input or output.
The TIM forces the I/O state to be an output for a timer port associated with an enabled output compare. Else the
routed PWM forces the I/O state to be an output for an enabled channel. In these cases the data direction bit will not
change.
1 Associated pin is configured as output
0 Associated pin is configured as input
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Freescale Semiconductor
73
Port Integration Module (S12PPIMV1)
2.3.19
Port T Reduced Drive Register (RDRT)
Access: User read/write(1)
Address 0x0243
7
6
5
4
3
2
1
0
RDRT7
RDRT6
RDRT5
RDRT4
RDRT3
RDRT2
RDRT1
RDRT0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-17. Port T Reduced Drive Register (RDRT)
1. Read: Anytime
Write: Anytime
Table 2-17. RDRT Register Field Descriptions
Field
Description
7-0
RDRT
Port T reduced drive—Select reduced drive for output pin
This bit configures the drive strength of the associated output pin as either full or reduced. If a pin is used as input
this bit has no effect. The reduced drive function is independent of which function is being used on a particular pin.
1 Reduced drive selected (approx. 1/5 of the full drive strength)
0 Full drive strength enabled
2.3.20
Port T Pull Device Enable Register (PERT)
Access: User read/write(1)
Address 0x0244
7
6
5
4
3
2
1
0
PERT7
PERT6
PERT5
PERT4
PERT3
PERT2
PERT1
PERT0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-18. Port T Pull Device Enable Register (PERT)
1. Read: Anytime
Write: Anytime
Table 2-18. PERT Register Field Descriptions
Field
Description
7-0
PERT
Port T pull device enable—Enable pull device on input pin
This bit controls whether a pull device on the associated port input pin is active. If a pin is used as output this bit has
no effect. The polarity is selected by the related polarity select register bit.
1 Pull device enabled
0 Pull device disabled
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.21
Port T Polarity Select Register (PPST)
Access: User read/write(1)
Address 0x0245
7
6
5
4
3
2
1
0
PPST7
PPST6
PPST5
PPST4
PPST3
PPST2
PPST1
PPST0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-19. Port T Polarity Select Register (PPST)
1. Read: Anytime
Write: Anytime
Table 2-19. PPST Register Field Descriptions
Field
7-0
PPST
Description
Port T pull device select—Configure pull device polarity on input pin
This bit selects a pull-up or a pull-down device if enabled on the associated port input pin.
1 A pull-down device is selected
0 A pull-up device is selected
2.3.22
PIM Reserved Register
Access: User read(1)
Address 0x0246
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 2-20. PIM Reserved Register
1. Read: Always reads 0x00
Write: Unimplemented
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Freescale Semiconductor
75
Port Integration Module (S12PPIMV1)
2.3.23
Port T Routing Register (PTTRR)
Access: User read(1)
Address 0x0247
R
7
6
0
0
5
4
PTTRR5
PTTRR4
3
2
1
0
0
0
0
PTTRR0
W
Routing
Option
—
—
PWM5
PWM4
—
—
—
PWM0
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 2-21. Port T Routing Register (PTTRR)
1. Read: Anytime
Write: Anytime
This register configures the re-routing of PWM channels on alternative pins on Port T.
Table 2-20. Port T Routing Register Field Descriptions
Field
5
PTTRR
Description
Port T data direction—
This register controls the routing of PWM channel 5.
1 PWM5 routed to PT5
0 PWM5 routed to PP5
4
PTTRR
Port T data direction—
This register controls the routing of PWM channel 4.
1 PWM4 routed to PT4
0 PWM4 routed to PP4
0
PTTRR
Port T data direction—
This register controls the routing of PWM channel 0.
1 PWM0 routed to PT0
0 PWM0 routed to PP0
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.24
Port S Data Register (PTS)
Access: User read/write(1)
Address 0x0248
R
7
6
5
4
0
0
0
0
3
2
1
0
PTS3
PTS2
PTS1
PTS0
W
Altern.
Function
—
—
—
—
—
—
TXD
RXD
Reset
0
0
0
0
0
0
0
0
Figure 2-22. Port S Data Register (PTS)
1. Read: Anytime The data source is depending on the data direction value.
Write: Anytime
Table 2-21. PTS Register Field Descriptions
Field
Description
3-2
PTS
Port S general purpose input/output data—Data Register
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
1
PTS
Port S general purpose input/output data—Data Register, SCI TXD output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The SCI function takes precedence over the general purpose I/O function if enabled.
0
PTS
Port S general purpose input/output data—Data Register, SCI RXD input
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The SCI function takes precedence over the general purpose I/O function if enabled.
2.3.25
Port S Input Register (PTIS)
Access: User read(1)
Address 0x0249
R
7
6
5
4
3
2
1
0
0
0
0
0
PTIS3
PTIS2
PTIS1
PTIS0
u
u
u
u
u
u
u
u
W
Reset
= Unimplemented or Reserved
u = Unaffected by reset
Figure 2-23. Port S Input Register (PTIS)
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
77
Port Integration Module (S12PPIMV1)
1. Read: Anytime
Write:Never, writes to this register have no effect.
Table 2-22. PTIS Register Field Descriptions
Field
Description
3-0
PTIS
Port S input data—
A read always returns the buffered input state of the associated pin. It can be used to detect overload or short circuit
conditions on output pins.
2.3.26
Port S Data Direction Register (DDRS)
Access: User read/write(1)
Address 0x024A
R
7
6
5
4
0
0
0
0
3
2
1
0
DDRS3
DDRS2
DDRS1
DDRS0
0
0
0
0
W
Reset
0
0
0
0
Figure 2-24. Port S Data Direction Register (DDRS)
1. Read: Anytime
Write: Anytime
Table 2-23. DDRS Register Field Descriptions
Field
3-2
DDRS
Description
Port S data direction—
This bit determines whether the associated pin is an input or output.
1 Associated pin is configured as output
0 Associated pin is configured as input
1
DDRS
Port S data direction—
This bit determines whether the associated pin is an input or output.
Depending on the configuration of the enabled SCI the I/O state will be forced to be input or output. In this case the
data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
0
DDRS
Port S data direction—
This bit determines whether the associated pin is an input or output.
Depending on the configuration of the enabled SCI the I/O state will be forced to be input or output. In this case the
data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.27
Port S Reduced Drive Register (RDRS)
Access: User read/write(1)
Address 0x024B
R
7
6
5
4
0
0
0
0
3
2
1
0
RDRS3
RDRS2
RDRS1
RDRS0
0
0
0
0
W
Reset
0
0
0
0
Figure 2-25. Port S Reduced Drive Register (RDRS)
1. Read: Anytime
Write: Anytime
Table 2-24. RDRS Register Field Descriptions
Field
Description
3-0
RDRS
Port S reduced drive—Select reduced drive for output pin
This bit configures the drive strength of the associated output pin as either full or reduced. If a pin is used as input
this bit has no effect. The reduced drive function is independent of which function is being used on a particular pin.
1 Reduced drive selected (approx. 1/5 of the full drive strength)
0 Full drive strength enabled
2.3.28
Port S Pull Device Enable Register (PERS)
Access: User read/write(1)
Address 0x024C
R
7
6
5
4
0
0
0
0
3
2
1
0
PERS3
PERS2
PERS1
PERS0
1
1
1
1
W
Reset
0
0
0
0
Figure 2-26. Port S Pull Device Enable Register (PERS)
1. Read: Anytime
Write: Anytime
Table 2-25. PERS Register Field Descriptions
Field
Description
3-0
PERS
Port S pull device enable—Enable pull device on input pin or wired-or output pin
This bit controls whether a pull device on the associated port input pin is active. If a pin is used as output this bit has
only effect if used in wired-or mode. The polarity is selected by the related polarity select register bit.
1 Pull device enabled
0 Pull device disabled
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Freescale Semiconductor
79
Port Integration Module (S12PPIMV1)
2.3.29
Port S Polarity Select Register (PPSS)
Access: User read/write(1)
Address 0x024D
R
7
6
5
4
0
0
0
0
3
2
1
0
PPSS3
PPSS2
PPSS1
PPSS0
0
0
0
0
W
Reset
0
0
0
0
Figure 2-27. Port S Polarity Select Register (PPSS)
1. Read: Anytime
Write: Anytime
Table 2-26. PPSS Register Field Descriptions
Field
3-0
PPSS
Description
Port S pull device select—Configure pull device polarity on input pin
This bit selects a pull-up or a pull-down device if enabled on the associated port input pin.
1 A pull-down device is selected
0 A pull-up device is selected
2.3.30
Port S Wired-Or Mode Register (WOMS)
Access: User read/write(1)
Address 0x024E
R
7
6
5
4
0
0
0
0
3
2
1
0
WOMS3
WOMS2
WOMS1
WOMS0
0
0
0
0
W
Reset
0
0
0
0
Figure 2-28. Port S Wired-Or Mode Register (WOMS)
1. Read: Anytime
Write: Anytime
Table 2-27. WOMS Register Field Descriptions
Field
Description
3-0
WOMS
Port S wired-or mode—Enable open-drain functionality on output pin
This bit configures an output pin as wired-or (open-drain) or push-pull. In wired-or mode a logic “0” is driven active
low while a logic “1” remains undriven. This allows a multipoint connection of several serial modules. The bit has no
influence on pins used as input.
1 Output buffer operates as open-drain output.
0 Output buffer operates as push-pull output.
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.31
PIM Reserved Register
Access: User read(1)
Address 0x024F
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
u = Unaffected by reset
Figure 2-29. PIM Reserved Register
1. Read: Always reads 0x00
Write: Unimplemented
2.3.32
Port M Data Register (PTM)
Access: User read/write(1)
Address 0x0250
R
7
6
0
0
5
4
3
2
1
0
PTM5
PTM4
PTM3
PTM2
PTM1
PTM0
W
Altern.
Function
—
—
SCK
MOSI
SS
MISO
TXCAN
RXCAN
Reset
0
0
0
0
0
0
0
0
Figure 2-30. Port M Data Register (PTM)
1. Read: Anytime. The data source is depending on the data direction value.
Write: Anytime
Table 2-28. PTM Register Field Descriptions
Field
Description
5
PTM
Port M general purpose input/output data—Data Register, SPI SCK input/output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The SPI function takes precedence over the general purpose I/O function if enabled.
4
PTM
Port M general purpose input/output data—Data Register, SPI MOSI input/output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The SPI function takes precedence over the general purpose I/O function if enabled.
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Freescale Semiconductor
81
Port Integration Module (S12PPIMV1)
Table 2-28. PTM Register Field Descriptions (continued)
Field
Description
3
PTM
Port M general purpose input/output data—Data Register, SPI SS input/output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The SPI function takes precedence over the general purpose I/O function if enabled.
2
PTM
Port M general purpose input/output data—Data Register, SPI MISO input/output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The SPI function takes precedence over the general purpose I/O function if enabled.
1
PTM
Port M general purpose input/output data—Data Register, CAN TXCAN output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The CAN function takes precedence over the general purpose I/O function if enabled.
0
PTM
Port M general purpose input/output data—Data Register, CAN RXCAN input
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The CAN function takes precedence over the general purpose I/O function if enabled.
2.3.33
Port M Input Register (PTIM)
Access: User read(1)
Address 0x0251
R
7
6
5
4
3
2
1
0
0
0
PTIM5
PTIM4
PTIM3
PTIM2
PTIM1
PTIM0
u
u
u
u
u
u
u
u
W
Reset
= Unimplemented or Reserved
u = Unaffected by reset
Figure 2-31. Port M Input Register (PTIM)
1. Read: Anytime
Write:Never, writes to this register have no effect.
S12P-Family Reference Manual, Rev. 1.13
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
Table 2-29. PTIM Register Field Descriptions
Field
Description
5-0
PTIM
Port M input data—
A read always returns the buffered input state of the associated pin. It can be used to detect overload or short circuit
conditions on output pins.
2.3.34
Port M Data Direction Register (DDRM)
Access: User read/write(1)
Address 0x0252
R
7
6
0
0
5
4
3
2
1
0
DDRM5
DDRM4
DDRM3
DDRM2
DDRM1
DDRM0
0
0
0
0
0
0
W
Reset
0
0
Figure 2-32. Port M Data Direction Register (DDRM)
1. Read: Anytime
Write: Anytime
Table 2-30. DDRM Register Field Descriptions
Field
Description
5
DDRM
Port M data direction—
This bit determines whether the associated pin is an input or output.
Depending on the configuration of the enabled SPI the I/O state will be forced to be input or output. In this case the
data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
4
DDRM
Port M data direction—
This bit determines whether the associated pin is an input or output.
Depending on the configuration of the enabled SPI the I/O state will be forced to be input or output. In this case the
data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
3
DDRM
Port M data direction—
This bit determines whether the associated pin is an input or output.
Depending on the configuration of the enabled SPI the I/O state will be forced to be input or output. In this case the
data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
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Freescale Semiconductor
83
Port Integration Module (S12PPIMV1)
Table 2-30. DDRM Register Field Descriptions (continued)
Field
Description
2
DDRM
Port M data direction—
This bit determines whether the associated pin is an input or output.
Depending on the configuration of the enabled SPI the I/O state will be forced to be input or output. In this case the
data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
1
DDRM
Port M data direction—
This bit determines whether the associated pin is an input or output.
The enabled CAN forces the I/O state to be an output. In this case the data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
0
DDRM
Port M data direction—
This bit determines whether the associated pin is an input or output.
The enabled CAN forces the I/O state to be an input. In this case the data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
2.3.35
Port M Reduced Drive Register (RDRM)
Access: User read/write(1)
Address 0x0253
R
7
6
0
0
5
4
3
2
1
0
RDRM5
RDRM4
RDRM3
RDRM2
RDRM1
RDRM0
0
0
0
0
0
0
W
Reset
0
0
Figure 2-33. Port M Reduced Drive Register (RDRM)
1. Read: Anytime
Write: Anytime
Table 2-31. RDRM Register Field Descriptions
Field
Description
5-0
RDRM
Port M reduced drive—Select reduced drive for output pin
This bit configures the drive strength of the associated output pin as either full or reduced. If a pin is used as input
this bit has no effect. The reduced drive function is independent of which function is being used on a particular pin.
1 Reduced drive selected (approx. 1/5 of the full drive strength)
0 Full drive strength enabled
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.36
Port M Pull Device Enable Register (PERM)
Access: User read/write(1)
Address 0x0254
R
7
6
0
0
5
4
3
2
1
0
PERM5
PERM4
PERM3
PERM2
PERM1
PERM0
0
0
0
0
0
0
W
Reset
0
0
Figure 2-34. Port M Pull Device Enable Register (PERM)
1. Read: Anytime
Write: Anytime
Table 2-32. PERM Register Field Descriptions
Field
Description
5-0
PERM
Port M pull device enable—Enable pull device on input pin or wired-or output pin
This bit controls whether a pull device on the associated port input pin is active. If a pin is used as output this bit has
only effect if used in wired-or mode. The polarity is selected by the related polarity select register bit.
1 Pull device enabled
0 Pull device disabled
2.3.37
Port M Polarity Select Register (PPSM)
Access: User read/write(1)
Address 0x0255
R
7
6
0
0
5
4
3
2
1
0
PPSM5
PPSM4
PPSM3
PPSM2
PPSM1
PPSM0
0
0
0
0
0
0
W
Reset
0
0
Figure 2-35. Port M Polarity Select Register (PPSM)
1. Read: Anytime
Write: Anytime
Table 2-33. PPSM Register Field Descriptions
Field
5-0
PPSM
Description
Port M pull device select—Configure pull device polarity on input pin
This bit selects a pull-up or a pull-down device if enabled on the associated port input pin.
If CAN is active the selection of a pull-down device on the RXCAN input will have no effect.
1 A pull-down device is selected
0 A pull-up device is selected
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Freescale Semiconductor
85
Port Integration Module (S12PPIMV1)
2.3.38
Port M Wired-Or Mode Register (WOMM)
Access: User read/write(1)
Address 0x0256
R
7
6
0
0
5
4
3
2
1
0
WOMM5
WOMM4
WOMM3
WOMM2
WOMM1
WOMM0
0
0
0
0
0
0
W
Reset
0
0
Figure 2-36. Port M Wired-Or Mode Register (WOMM)
1. Read: Anytime
Write: Anytime
Table 2-34. WOMM Register Field Descriptions
Field
Description
5-0
WOMM
Port M wired-or mode—Enable open-drain functionality on output pin
This bit configures an output pin as wired-or (open-drain) or push-pull. In wired-or mode a logic “0” is driven active
low while a logic “1” remains undriven. This allows a multipoint connection of several serial modules. The bit has no
influence on pins used as input.
1 Output buffer operates as open-drain output.
0 Output buffer operates as push-pull output.
2.3.39
PIM Reserved Register
Access: User read(1)
Address 0x0257
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
u = Unaffected by reset
Figure 2-37. PIM Reserved Register
1. Read: Always reads 0x00
Write: Unimplemented
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.40
Port P Data Register (PTP)
Access: User read/write(1)
Address 0x0258
7
R
6
5
4
3
2
1
0
PTP5
PTP4
PTP3
PTP2
PTP1
PTP0
0
PTP7
W
Altern.
Function
—
—
PWM5
PWM4
PWM3
PWM2
PWM1
PWM0
Reset
0
0
0
0
0
0
0
0
Figure 2-38. Port P Data Register (PTP)
1. Read: Anytime. The data source is depending on the data direction value.
Write: Anytime
Table 2-35. PTP Register Field Descriptions
Field
Description
7
PTP
Port P general purpose input/output data—Data Register, pin interrupt input/output
The associated pin can be used as general purpose I/O. In general purpose output mode the register bit value is
driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• Pin interrupts can be generated if enabled in input or output mode.
5
PTP
Port P general purpose input/output data—Data Register, PWM input/output, pin interrupt input/output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The PWM function takes precedence over the general purpose I/O function if the related channel or the
emergency shut-down feature is enabled.
• Pin interrupts can be generated if enabled in input or output mode.
4-0
PTP
Port P general purpose input/output data—Data Register, PWM output, pin interrupt input/output
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• The PWM function takes precedence over the general purpose I/O function if the related channel is enabled.
• Pin interrupts can be generated if enabled in input or output mode.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
87
Port Integration Module (S12PPIMV1)
2.3.41
Port P Input Register (PTIP)
Access: User read(1)
Address 0x0259
R
7
6
5
4
3
2
1
0
PTIP7
0
PTIP5
PTIP4
PTIP3
PTIP2
PTIP1
PTIP0
u
u
u
u
u
u
u
u
W
Reset
= Unimplemented or Reserved
u = Unaffected by reset
Figure 2-39. Port P Input Register (PTIP)
1. Read: Anytime
Write:Never, writes to this register have no effect.
Table 2-36. PTIP Register Field Descriptions
Field
Description
7,5-0
PTIP
Port P input data—
A read always returns the buffered input state of the associated pin. It can be used to detect overload or short circuit
conditions on output pins.
2.3.42
Port P Data Direction Register (DDRP)
Access: User read/write(1)
Address 0x025A
7
R
6
5
4
3
2
1
0
DDRP5
DDRP4
DDRP3
DDRP2
DDRP1
DDRP0
0
0
0
0
0
0
0
DDRP7
W
Reset
0
0
Figure 2-40. Port P Data Direction Register (DDRP)
1. Read: Anytime
Write: Anytime
Table 2-37. DDRP Register Field Descriptions
Field
7
DDRP
Description
Port P data direction—
This bit determines whether the associated pin is an input or output.
1 Associated pin is configured as output
0 Associated pin is configured as input
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
Table 2-37. DDRP Register Field Descriptions (continued)
Field
Description
5
DDRP
Port P data direction—
This bit determines whether the associated pin is an input or output.
The PWM forces the I/O state to be an output for an enabled channel. If the emergency shut-down feature is enabled
this pin is an input. In this case the data direction bit will not change.
1 Associated pin is configured as output
0 Associated pin is configured as input
4-0
DDRP
Port P data direction—
This bit determines whether the associated pin is an input or output.
The PWM forces the I/O state to be an output for an enabled channel. In this case the data direction bit will not
change.
1 Associated pin is configured as output
0 Associated pin is configured as input
2.3.43
Port P Reduced Drive Register (RDRP)
Access: User read/write(1)
Address 0x025B
7
R
6
5
4
3
2
1
0
RDRP5
RDRP4
RDRP3
RDRP2
RDRP1
RDRP0
0
0
0
0
0
0
0
RDRP7
W
Reset
0
0
Figure 2-41. Port P Reduced Drive Register (RDRP)
1. Read: Anytime
Write: Anytime
Table 2-38. RDRP Register Field Descriptions
Field
Description
7,5-0
RDRP
Port P reduced drive—Select reduced drive for output pin
This bit configures the drive strength of the associated output pin as either full or reduced. If a pin is used as input
this bit has no effect. The reduced drive function is independent of which function is being used on a particular pin.
1 Reduced drive selected (approx. 1/5 of the full drive strength)
0 Full drive strength enabled
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Freescale Semiconductor
89
Port Integration Module (S12PPIMV1)
2.3.44
Port P Pull Device Enable Register (PERP)
Access: User read/write(1)
Address 0x025C
7
R
6
5
4
3
2
1
0
PPSP5
PPSP4
PPSP3
PPSP2
PPSP1
PPSP0
0
0
0
0
0
0
0
PPSP7
W
Reset
0
0
Figure 2-42. Port P Pull Device Enable Register (PERP)
1. Read: Anytime
Write: Anytime
Table 2-39. PERP Register Field Descriptions
Field
Description
7,5-0
PERP
Port P pull device enable—Enable pull device on input pin
This bit controls whether a pull device on the associated port input pin is active. If a pin is used as output this bit has
no effect. The polarity is selected by the related polarity select register bit.
1 Pull device enabled
0 Pull device disabled
2.3.45
Port P Polarity Select Register (PPSP)
Access: User read/write(1)
Address 0x025D
7
R
6
5
4
3
2
1
0
PPSP5
PPSP4
PPSP3
PPSP2
PPSP1
PPSP0
0
0
0
0
0
0
0
PPSP7
W
Reset
0
0
Figure 2-43. Port P Polarity Select Register (PPSP)
1. Read: Anytime
Write: Anytime
Table 2-40. PPSP Register Field Descriptions
Field
7,5-0
PPSP
Description
Port P pull device select—Configure pull device and pin interrupt edge polarity on input pin
This bit selects a pull-up or a pull-down device if enabled on the associated port input pin.
This bit also selects the polarity of the active pin interrupt edge.
1 A pull-down device is selected; rising edge selected
0 A pull-up device is selected; falling edge selected
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90
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.46
Port P Interrupt Enable Register (PIEP)
Read: Anytime.
Access: User read/write(1)
Address 0x025E
7
R
6
5
4
3
2
1
0
PIEP5
PIEP4
PIEP3
PIEP2
PIEP1
PIEP0
0
0
0
0
0
0
0
PIEP7
W
Reset
0
0
Figure 2-44. Port P Interrupt Enable Register (PIEP)
1. Read: Anytime
Write: Anytime
Table 2-41. PIEP Register Field Descriptions
Field
7,5-0
PIEP
Description
Port P interrupt enable—
This bit enables or disables on the edge sensitive pin interrupt on the associated pin.
1 Interrupt is enabled
0 Interrupt is disabled (interrupt flag masked)
2.3.47
Port P Interrupt Flag Register (PIFP)
Access: User read/write(1)
Address 0x025F
7
R
6
5
4
3
2
1
0
PIFP5
PIFP4
PIFP3
PIFP2
PIFP1
PIFP0
0
0
0
0
0
0
0
PIFP7
W
Reset
0
0
Figure 2-45. Port P Interrupt Flag Register (PIFP)
1. Read: Anytime
Write: Anytime
Table 2-42. PIFP Register Field Descriptions
Field
Description
7,5-0
PIFP
Port P interrupt flag—
The flag bit is set after an active edge was applied to the associated input pin. This can be a rising or a falling edge
based on the state of the polarity select register.
Writing a logic “1” to the corresponding bit field clears the flag.
1 Active edge on the associated bit has occurred (an interrupt will occur if the associated enable bit is set)
0 No active edge occurred
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
91
Port Integration Module (S12PPIMV1)
2.3.48
PIM Reserved Registers
Access: User read(1)
Address 0x0260-0x267
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
u = Unaffected by reset
Figure 2-46. PIM Reserved Registers
1. Read: Always reads 0x00
Write: Unimplemented
2.3.49
Port J Data Register (PTJ)
Access: User read/write(1)
Address 0x0268
7
6
PTJ7
PTJ6
0
0
R
5
4
3
0
0
0
2
1
0
PTJ2
PTJ1
PTJ0
0
0
0
W
Reset
0
0
0
Figure 2-47. Port J Data Register (PTJ)
1. Read: Anytime. The data source is depending on the data direction value.
Write: Anytime
Table 2-43. PTJ Register Field Descriptions
Field
Description
7-6, 2-0
PTJ
Port J general purpose input/output data—Data Register, pin interrupt input/output
The associated pin can be used as general purpose I/O. In general purpose output mode the register bit value is
driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
• Pin interrupts can be generated if enabled in input or output mode.
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92
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.50
Port J Input Register (PTIJ)
Access: User read(1)
Address 0x0269
R
7
6
5
4
3
2
1
0
PTIJ7
PTIJ6
0
0
0
PTIJ2
PTIJ1
PTIJ0
u
u
u
u
u
u
u
u
W
Reset
= Unimplemented or Reserved
u = Unaffected by reset
Figure 2-48. Port J Input Register (PTIJ)
1. Read: Anytime
Write:Never, writes to this register have no effect.
Table 2-44. PTIJ Register Field Descriptions
Field
Description
7-6, 2-0
PTIJ
Port J input data—
A read always returns the buffered input state of the associated pin. It can be used to detect overload or short circuit
conditions on output pins.
2.3.51
Port J Data Direction Register (DDRJ)
Access: User read/write(1)
Address 0x026A
7
6
DDRJ7
DDRJ6
0
0
R
5
4
3
0
0
0
2
1
0
DDRJ2
DDRJ1
DDRJ0
0
0
0
W
Reset
0
0
0
Figure 2-49. Port J Data Direction Register (DDRJ)
1. Read: Anytime
Write: Anytime
Table 2-45. DDRJ Register Field Descriptions
Field
7-6, 2-0
DDRJ
Description
Port J data direction—
This bit determines whether the associated pin is an input or output.
1 Associated pin is configured as output
0 Associated pin is configured as input
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Freescale Semiconductor
93
Port Integration Module (S12PPIMV1)
2.3.52
Port J Reduced Drive Register (RDRJ)
Access: User read/write(1)
Address 0x026B
7
6
RDRJ7
RDRJ6
0
0
R
5
4
3
0
0
0
2
1
0
RDRJ2
RDRJ1
RDRJ0
0
0
0
W
Reset
0
0
0
Figure 2-50. Port J Reduced Drive Register (RDRJ)
1. Read: Anytime
Write: Anytime
Table 2-46. RDRJ Register Field Descriptions
Field
Description
7-6, 2-0
RDRJ
Port J reduced drive—Select reduced drive for output pin
This bit configures the drive strength of the associated output pin as either full or reduced. If a pin is used as input
this bit has no effect. The reduced drive function is independent of which function is being used on a particular pin.
1 Reduced drive selected (approx. 1/5 of the full drive strength)
0 Full drive strength enabled
2.3.53
Port J Pull Device Enable Register (PERJ)
Access: User read/write(1)
Address 0x026C
7
6
PERJ7
PERJ6
1
1
R
5
4
3
0
0
0
2
1
0
PERJ2
PERJ1
PERJ0
1
1
1
W
Reset
0
0
0
Figure 2-51. Port J Pull Device Enable Register (PERJ)
1. Read: Anytime
Write: Anytime
Table 2-47. PERJ Register Field Descriptions
Field
Description
7-6, 2-0
PERJ
Port J pull device enable—Enable pull device on input pin
This bit controls whether a pull device on the associated port input pin is active. If a pin is used as output this bit has
no effect. The polarity is selected by the related polarity select register bit.
1 Pull device enabled
0 Pull device disabled
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94
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.54
Port J Polarity Select Register (PPSJ)
Access: User read/write(1)
Address 0x026D
7
6
PPSJ7
PPSJ6
0
0
R
5
4
3
0
0
0
2
1
0
PPSJ2
PPSJ1
PPSJ0
0
0
0
W
Reset
0
0
0
Figure 2-52. Port J Polarity Select Register (PPSJ)
1. Read: Anytime
Write: Anytime
Table 2-48. PPSJ Register Field Descriptions
Field
7-6, 2-0
PPSJ
Description
Port J pull device select—Configure pull device and pin interrupt edge polarity on input pin
This bit selects a pull-up or a pull-down device if enabled on the associated port input pin.
This bit also selects the polarity of the active pin interrupt edge.
1 A pull-down device is selected; rising edge selected
0 A pull-up device is selected; falling edge selected
2.3.55
Port J Interrupt Enable Register (PIEJ)
Read: Anytime.
Access: User read/write(1)
Address 0x026E
7
6
PIEJ7
PIEJ6
0
0
R
5
4
3
0
0
0
2
1
0
PIEJ2
PIEJ1
PIEJ0
0
0
0
W
Reset
0
0
0
Figure 2-53. Port J Interrupt Enable Register (PIEJ)
1. Read: Anytime
Write: Anytime
Table 2-49. PIEJ Register Field Descriptions
Field
7-6, 2-0
PIEJ
Description
Port J interrupt enable—
This bit enables or disables on the edge sensitive pin interrupt on the associated pin.
1 Interrupt is enabled
0 Interrupt is disabled (interrupt flag masked)
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
95
Port Integration Module (S12PPIMV1)
2.3.56
Port J Interrupt Flag Register (PIFJ)
Access: User read/write(1)
Address 0x026F
7
6
PIFJ7
PIFJ6
0
0
R
5
4
3
0
0
0
2
1
0
PIFJ2
PIFJ1
PIFJ0
0
0
0
W
Reset
0
0
0
Figure 2-54. Port J Interrupt Flag Register (PIFJ)
1. Read: Anytime
Write: Anytime
Table 2-50. PIFJ Register Field Descriptions
Field
Description
7-6, 2-0
PIFJ
Port J interrupt flag—
The flag bit is set after an active edge was applied to the associated input pin. This can be a rising or a falling edge
based on the state of the polarity select register.
Writing a logic “1” to the corresponding bit field clears the flag.
1 Active edge on the associated bit has occurred (an interrupt will occur if the associated enable bit is set)
0 No active edge occurred
2.3.57
Port AD Data Register (PT0AD)
Access: User read/write(1)
Address 0x0270
R
7
6
5
4
3
2
0
0
0
0
0
0
1
0
PT0AD1
PT0AD0
W
Altern.
Function
—
—
—
—
—
—
AN9
AN8
Reset
0
0
0
0
0
0
0
0
Figure 2-55. Port AD Data Register (PT0AD)
1. Read: Anytime. The data source is depending on the data direction value.
Write: Anytime
Table 2-51. PT0AD Register Field Descriptions
Field
Description
1-0
PT0AD
Port AD general purpose input/output data—Data Register, ATD AN analog input
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
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96
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.58
Port AD Data Register (PT1AD)
Access: User read/write(1)
Address 0x0271
7
6
5
4
3
2
1
0
PT1AD7
PT1AD6
PT1AD5
PT1AD4
PT1AD3
PT1AD2
PT1AD1
PT1AD0
AN7
AN6
AN5
AN4
AN3
AN2
AN1
AN0
0
0
0
0
0
0
0
0
R
W
Altern.
Function
Reset
Figure 2-56. Port AD Data Register (PT1AD)
1. Read: Anytime. The data source is depending on the data direction value.
Write: Anytime
Table 2-52. PT1AD Register Field Descriptions
Field
Description
7-0
PT1AD
Port AD general purpose input/output data—Data Register, ATD AN analog input
When not used with the alternative function, the associated pin can be used as general purpose I/O. In general
purpose output mode the register bit value is driven to the pin.
If the associated data direction bit is set to 1, a read returns the value of the port register bit, otherwise the buffered
pin input state is read.
2.3.59
Port AD Data Direction Register (DDR0AD)
Access: User read/write(1)
Address 0x0272
R
7
6
5
4
3
2
0
0
0
0
0
0
1
0
DDR0AD1
DDR0AD0
0
0
W
Reset
0
0
0
0
0
0
Figure 2-57. Port AD Data Direction Register (DDR0AD)
1. Read: Anytime
Write: Anytime
Table 2-53. DDR0AD Register Field Descriptions
Field
1-0
DDR0AD
Description
Port AD data direction—
This bit determines whether the associated pin is an input or output.
To use the digital input function the ATD Digital Input Enable Register (ATDDIEN) has to be set to logic level “1”.
1 Associated pin is configured as output
0 Associated pin is configured as input
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Freescale Semiconductor
97
Port Integration Module (S12PPIMV1)
2.3.60
Port AD Data Direction Register (DDR1AD)
Access: User read/write(1)
Address 0x0273
7
6
5
4
3
2
1
0
DDR1AD7
DDR1AD6
DDR1AD5
DDR1AD4
DDR1AD3
DDR1AD2
DDR1AD1
DDR1AD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-58. Port AD Data Direction Register (DDR1AD)
1. Read: Anytime
Write: Anytime
Table 2-54. DDR1AD Register Field Descriptions
Field
7-0
DDR1AD
Description
Port AD data direction—
This bit determines whether the associated pin is an input or output.
To use the digital input function the ATD Digital Input Enable Register (ATDDIEN) has to be set to logic level “1”.
1 Associated pin is configured as output
0 Associated pin is configured as input
2.3.61
Port AD Reduced Drive Register (RDR0AD)
Access: User read/write(1)
Address 0x0274
R
7
6
5
4
3
2
0
0
0
0
0
0
1
0
RDR0AD1
RDR0AD0
0
0
W
Reset
0
0
0
0
0
0
Figure 2-59. Port AD Reduced Drive Register (RDR0AD)
1. Read: Anytime
Write: Anytime
Table 2-55. RDR0AD Register Field Descriptions
Field
Description
1-0
RDR0AD
Port AD reduced drive—Select reduced drive for output pin
This bit configures the drive strength of the associated output pin as either full or reduced. If a pin is used as input
this bit has no effect. The reduced drive function is independent of which function is being used on a particular pin.
1 Reduced drive selected (approx. 1/5 of the full drive strength)
0 Full drive strength enabled
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98
Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.3.62
Port AD Reduced Drive Register (RDR1AD)
Access: User read/write(1)
Address 0x0275
7
6
5
4
3
2
1
0
RDR1AD7
RDR1AD6
RDR1AD5
RDR1AD4
RDR1AD3
RDR1AD2
RDR1AD1
RDR1AD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-60. Port AD Reduced Drive Register (RDR1AD)
1. Read: Anytime
Write: Anytime
Table 2-56. RDR1AD Register Field Descriptions
Field
Description
7-0
RDR1AD
Port AD reduced drive—Select reduced drive for output pin
This bit configures the drive strength of the associated output pin as either full or reduced. If a pin is used as input
this bit has no effect. The reduced drive function is independent of which function is being used on a particular pin.
1 Reduced drive selected (approx. 1/5 of the full drive strength)
0 Full drive strength enabled
2.3.63
Port AD Pull Up Enable Register (PER0AD)
Access: User read/write(1)
Address 0x0276
R
7
6
5
4
3
2
0
0
0
0
0
0
1
0
PER0AD1
PER0AD0
0
0
W
Reset
0
0
0
0
0
0
Figure 2-61. Port AD Pull Up Enable Register (PER0AD)
1. Read: Anytime
Write: Anytime
Table 2-57. PER0AD Register Field Descriptions
Field
Description
1-0
PER0AD
Port AD pull-up enable—Enable pull-up device on input pin
This bit controls whether a pull device on the associated port input pin is active. If a pin is used as output this bit has
no effect.
1 Pull device enabled
0 Pull device disabled
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Freescale Semiconductor
99
Port Integration Module (S12PPIMV1)
2.3.64
Port AD Pull Up Enable Register (PER1AD)
Access: User read/write(1)
Address 0x0277
7
6
5
4
3
2
1
0
PER1AD7
PER1AD6
PER1AD5
PER1AD4
PER1AD3
PER1AD2
PER1AD1
PER1AD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 2-62. Port AD Pull Up Enable Register (PER1AD)
1. Read: Anytime
Write: Anytime
Table 2-58. PER1AD Register Field Descriptions
Field
Description
7-0
PER1AD
Port AD pull-up enable—Enable pull-up device on input pin
This bit controls whether a pull device on the associated port input pin is active. If a pin is used as output this bit has
no effect.
1 Pull device enabled
0 Pull device disabled
2.3.65
PIM Reserved Registers
Access: User read(1)
Address 0x0278-0x27F
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
u = Unaffected by reset
Figure 2-63. PIM Reserved Registers
1. Read: Always reads 0x00
Write: Unimplemented
2.4
2.4.1
Functional Description
General
Each pin except PE0, PE1, and BKGD can act as general purpose I/O. In addition each pin can act as an
output or input of a peripheral module.
2.4.2
Registers
A set of configuration registers is common to all ports with exception of the ATD port (Table 2-59). All
registers can be written at any time, however a specific configuration might not become active.
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
For example selecting a pull-up device: This device does not become active while the port is used as a
push-pull output.
Table 2-59. Register availability per port(1)
Data
Reduced
Direction
Drive
Pull
Enable
Polarity
Select
WiredOr Mode
Interrupt
Enable
Interrupt
Flag
Routing
yes
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
yes
-
-
-
yes
Port
Data
Input
A
yes
-
yes
B
yes
-
yes
E
yes
-
yes
T
yes
yes
yes
yes
yes
yes
S
yes
yes
yes
yes
yes
yes
yes
-
-
-
M
yes
yes
yes
yes
yes
yes
yes
-
-
yes
P
yes
yes
yes
yes
yes
yes
-
yes
yes
-
J
yes
yes
yes
yes
yes
yes
-
yes
yes
-
-
-
-
-
-
AD
yes
yes
yes
yes
1. Each cell represents one register with individual configuration bits
2.4.2.1
Data register (PORTx, PTx)
This register holds the value driven out to the pin if the pin is used as a general purpose I/O.
Writing to this register has only an effect on the pin if the pin is used as general purpose output. When
reading this address, the buffered state of the pin is returned if the associated data direction register bit is
set to “0”.
If the data direction register bits are set to logic level “1”, the contents of the data register is returned. This
is independent of any other configuration (Figure 2-64).
2.4.2.2
Input register (PTIx)
This register is read-only and always returns the buffered state of the pin (Figure 2-64).
2.4.2.3
Data direction register (DDRx)
This register defines whether the pin is used as an general purpose input or an output.
If a peripheral module controls the pin the contents of the data direction register is ignored (Figure 2-64).
Independent of the pin usage with a peripheral module this register determines the source of data when
reading the associated data register address (2.4.2.1/2-101).
NOTE
Due to internal synchronization circuits, it can take up to 2 bus clock cycles
until the correct value is read on port data or port input registers, when
changing the data direction register.
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Freescale Semiconductor
101
Port Integration Module (S12PPIMV1)
PTI
0
1
PT
0
PIN
1
DDR
0
1
data out
Module
output enable
module enable
Figure 2-64. Illustration of I/O pin functionality
2.4.2.4
Reduced drive register (RDRx)
If the pin is used as an output this register allows the configuration of the drive strength independent of the
use with a peripheral module.
2.4.2.5
Pull device enable register (PERx)
This register turns on a pull-up or pull-down device on the related pins determined by the associated
polarity select register (2.4.2.6/2-102).
The pull device becomes active only if the pin is used as an input or as a wired-or output. Some peripheral
module only allow certain configurations of pull devices to become active. Refer to the respective bit
descriptions.
2.4.2.6
Polarity select register (PPSx)
This register selects either a pull-up or pull-down device if enabled.
It becomes only active if the pin is used as an input. A pull-up device can be activated if the pin is used as
a wired-or output.
2.4.2.7
Wired-or mode register (WOMx)
If the pin is used as an output this register turns off the active high drive. This allows wired-or type
connections of outputs.
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Freescale Semiconductor
Port Integration Module (S12PPIMV1)
2.4.2.8
Interrupt enable register (PIEx)
If the pin is used as an interrupt input this register serves as a mask to the interrupt flag to enable/disable
the interrupt.
2.4.2.9
Interrupt flag register (PIFx)
If the pin is used as an interrupt input this register holds the interrupt flag after a valid pin event.
2.4.2.10
Module routing register (PTTRR)
This register allows software re-configuration of the pinouts of the different package options for specific
peripherals:
•
PTTRR supports the re-routing of the PWM channels to alternative ports
2.4.3
Pins and Ports
NOTE
Please refer to the device pinout section to determine the pin availability in
the different package options.
2.4.3.1
BKGD pin
The BKGD pin is associated with the BDM module.
During reset, the BKGD pin is used as MODC input.
2.4.3.2
Port A, B
Port A pins PA[7:0] and Port B pins PB[7:0] can be used for general purpose I/O.
2.4.3.3
Port E
Port E is associated with the free-running clock outputs ECLK, ECLKX2 and interrupt inputs IRQ and
XIRQ.
Port E pins PE[6:5,3:2] can be used for either general purpose I/O or with the alternative functions.
Port E pin PE[7] an be used for either general purpose I/O or as the free-running clock ECLKX2 output
running at the core clock rate.
Port E pin PE[4] an be used for either general purpose I/O or as the free-running clock ECLK output
running at the bus clock rate or at the programmed divided clock rate.
Port E pin PE[1] can be used for either general purpose input or as the level- or falling edge-sensitive IRQ
interrupt input. IRQ will be enabled by setting the IRQEN configuration bit (2.3.14/2-70) and clearing the
I-bit in the CPU condition code register. It is inhibited at reset so this pin is initially configured as a simple
input with a pull-up.
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Freescale Semiconductor
103
Port Integration Module (S12PPIMV1)
Port E pin PE[0] can be used for either general purpose input or as the level-sensitive XIRQ interrupt input.
XIRQ can be enabled by clearing the X-bit in the CPU condition code register. It is inhibited at reset so
this pin is initially configured as a high-impedance input with a pull-up.
2.4.3.4
Port T
This port is associated with TIM and PWM.
Port T pins PT[5:4,0] can be used for either general purpose I/O, or with the routed PWM or with the
channels of the standard Timer subsystem.
Port T pins PT[7:6,3:1] can be used for either general purpose I/O, or with the channels of the standard
Timer subsystem.
2.4.3.5
Port S
This port is associated with SCI.
Port S pins PS[1:0] can be used either for general purpose I/O, or with the SCI subsystem.
Port S pins PS[3:2] can be used for general purpose I/O.
2.4.3.6
Port M
This port is associated with CAN and SPI.
Port M pins PM[1:0] can be used for either general purpose I/O, or with the CAN subsystem.
Port M pins PM[5:2] can be used for general purpose I/O, or with the SPI subsystem.
2.4.3.7
Port P
This port is associated with the PWM.
Port P pins PP[7,5:0] can be used for either general purpose I/O with pin interrupt capability, or with the
PWM subsystem.
2.4.3.8
Port J
Port J pins PJ[7:6,2:0] can be used for general purpose I/O with pin-interrupt capability.
2.4.3.9
Port AD
This port is associated with the ATD.
Port AD pins PAD[9:0] can be used for either general purpose I/O, or with the ATD subsystem.
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Port Integration Module (S12PPIMV1)
2.4.4
Pin interrupts
Ports P and J offer pin interrupt capability. The interrupt enable as well as the sensitivity to rising or falling
edges can be individually configured on per-pin basis. All bits/pins in a port share the same interrupt
vector. Interrupts can be used with the pins configured as inputs or outputs.
An interrupt is generated when a bit in the port interrupt flag register and its corresponding port interrupt
enable bit are both set. The pin interrupt feature is also capable to wake up the CPU when it is in STOP or
WAIT mode.
A digital filter on each pin prevents pulses (Figure 2-66) shorter than a specified time from generating an
interrupt. The minimum time varies over process conditions, temperature and voltage (Figure 2-65 and
Table 2-60).
Glitch, filtered out, no interrupt flag set
Valid pulse, interrupt flag set
uncertain
tpign
tpval
Figure 2-65. Interrupt Glitch Filter on Port P and J (PPS=0)
Table 2-60. Pulse Detection Criteria
Mode
Pulse
STOP(1)
STOP
Unit
Ignored
Uncertain
Valid
tpulse ≤ 3
bus clocks
tpulse ≤ tpign
3 < tpulse < 4
bus clocks
tpign < tpulse < tpval
tpulse ≥ 4
bus clocks
tpulse ≥ tpval
1. These values include the spread of the oscillator frequency over temperature,
voltage and process.
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Port Integration Module (S12PPIMV1)
tpulse
Figure 2-66. Pulse Illustration
A valid edge on an input is detected if 4 consecutive samples of a passive level are followed by 4
consecutive samples of an active level directly or indirectly.
The filters are continuously clocked by the bus clock in RUN and WAIT mode. In STOP mode the clock
is generated by an RC-oscillator in the Port Integration Module. To maximize current saving the RC
oscillator runs only if the following condition is true on any pin individually:
Sample count <= 4 and interrupt enabled (PIE=1) and interrupt flag not set (PIF=0).
2.5
2.5.1
Initialization Information
Port Data and Data Direction Register writes
It is not recommended to write PORTx/PTx and DDRx in a word access. When changing the register pins
from inputs to outputs, the data may have extra transitions during the write access. Initialize the port data
register before enabling the outputs.
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Chapter 3
Memory Map Control (S12PMMCV1)
Table 3-1. Revision History Table
Table 3-2.
Rev. No.
Date
(Item No.) (Submitted By)
Sections
Affected
Substantial Change(s)
01.03
10.JAN.2008
General
Minor Changes
01.04
13.JAN.2010
Figure 3-2
Added reserved registers
01.05
22.APR.2010
General
Removed references to the MMCCTL1 register
3.1
Introduction
The S12PMMC module controls the access to all internal memories and peripherals for the CPU12 and
S12SBDM module. It regulates access priorities and determines the address mapping of the on-chip
ressources. Figure 3-1 shows a block diagram of the S12PMMC module.
3.1.1
Glossary
Table 3-3. Glossary Of Terms
Term
Definition
Local Addresses
Address within the CPU12’s Local Address Map (Figure 3-10)
Global Addresse
Address within the Global Address Map (Figure 3-10)
Aligned Bus Access
Bus access to an even address.
Misaligned Bus Access
Bus access to an odd address.
NS
Normal Single-Chip Mode
SS
Special Single-Chip Mode
Unimplemented Address Ranges
Address ranges which are not mapped to any on-chip ressource.
P-Flash
Program Flash
D-Plash
Data Flash
NVM
Non-volatile Memory; P-Flash or D-Flash
IFR
NVM Information Row. Refer to FTMRC Block Guide
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Memory Map Control (S12PMMCV1)
3.1.2
Overview
The S12PMMC connects the CPU12’s and the S12SBDM’s bus interfaces to the MCU’s on-chip
ressources (memories and peripherals). It arbitrates the bus accesses and detemines all of the MCU’s
memory maps. Furthermore, the S12PMMC is responsible for constraining memory accesses on secured
devices and for selecting the MCU’s functional mode.
3.1.3
Features
The main features of this block are:
• Paging capability to support a global 256 KByte memory address space
• Bus arbitration between the masters CPU12, S12SBDM to different resources.
• MCU operation mode control
• MCU security control
• Separate memory map schemes for each master CPU12, S12SBDM
• Generation of system reset when CPU12 accesses an unimplemented address (i.e., an address
which does not belong to any of the on-chip modules) in single-chip modes
3.1.4
Modes of Operation
The S12PMMC selects the MCU’s functional mode. It also determines the devices behavior in secured and
unsecured state.
3.1.4.1
Functional Modes
Two funtional modes are implementes on devices of the S12I product family:
• Normal Single Chip (NS)
The mode used for running applications.
• Special Single Chip Mode (SS)
A debug mode which causes the device to enter BDM Active Mode after each reset. Peripherals
may also provide special debug features in this mode.
3.1.4.2
Security
S12I devives can be secured to prohibit external access to the on-chip P-Flash. The S12PMMC module
determines the access permissions to the on-chip memories in secured and unsecured state.
3.1.5
Block Diagram
Figure 3-1 shows a block diagram of the S12PMMC.
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Memory Map Control (S12PMMCV1)
CPU
BDM
MMC
Address Decoder & Priority
DBG
Target Bus Controller
D-Flash
P-Flash
RAM
Peripherals
Figure 3-1. S12PMMC Block Diagram
3.2
External Signal Description
The S12PMMC uses two external pins to determine the devices operating mode: RESET and MODC
(Table 3-4) See Device User Guide (DUG) for the mapping of these signals to device pins.
Table 3-4. External System Pins Associated With S12PMMC
Pin Name
Pin Functions
RESET
(See DUG)
RESET
MODC
(See DUG)
MODC
3.3
3.3.1
Description
The RESET pin is used the select the MCU’s operating mode.
The MODC pin is captured at the rising edge of the RESET pin. The captured
value determines the MCU’s operating mode.
Memory Map and Registers
Module Memory Map
A summary of the registers associated with the S12PMMC block is shown in Figure 3-2. Detailed
descriptions of the registers and bits are given in the subsections that follow.
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Memory Map Control (S12PMMCV1)
Address
Register
Name
0x000A
Reserved
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
DP15
DP14
DP13
DP12
DP11
DP10
DP9
DP8
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
PIX3
PIX2
PIX1
PIX0
R
W
0x000B
MODE
R
MODC
W
0x0010
Reserved
R
W
0x0011
DIRECT
R
W
0x0012
Reserved
R
W
0x0013
Reserved
R
W
0x0014
Reserved
R
W
0x0015
PPAGE
R
W
= Unimplemented or Reserved
Figure 3-2. MMC Register Summary
3.3.2
Register Descriptions
This section consists of the S12PMMC control register descriptions in address order.
3.3.2.1
Mode Register (MODE)
Address: 0x000B
7
R
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
MODC
W
Reset
MODC1
1. External signal (see Table 3-4).
= Unimplemented or Reserved
Figure 3-3. Mode Register (MODE)
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Read: Anytime.
Write: Only if a transition is allowed (see Figure 3-4).
The MODC bit of the MODE register is used to select the MCU’s operating mode.
Table 3-5. MODE Field Descriptions
Field
Description
7
MODC
Mode Select Bit — This bit controls the current operating mode during RESET high (inactive). The external
mode pin MODC determines the operating mode during RESET low (active). The state of the pin is registered
into the respective register bit after the RESET signal goes inactive (see Figure 3-4).
Write restrictions exist to disallow transitions between certain modes. Figure 3-4 illustrates all allowed mode
changes. Attempting non authorized transitions will not change the MODE bit, but it will block further writes to
the register bit except in special modes.
Write accesses to the MODE register are blocked when the device is secured.
RESET
1
0
Normal
Single-Chip
(NS)
1
Special
Single-Chip
(SS)
1
0
Figure 3-4. Mode Transition Diagram when MCU is Unsecured
3.3.2.2
Direct Page Register (DIRECT)
Address: 0x0011
7
6
5
4
3
2
1
0
DP15
DP14
DP13
DP12
DP11
DP10
DP9
DP8
0
0
0
0
0
0
0
0
R
W
Reset
Figure 3-5. Direct Register (DIRECT)
Read: Anytime
Write: anytime in special SS, writr-one in NS.
This register determines the position of the 256 Byte direct page within the memory map.It is valid for both
global and local mapping scheme.
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Memory Map Control (S12PMMCV1)
Table 3-6. DIRECT Field Descriptions
Field
Description
7–0
DP[15:8]
Direct Page Index Bits 15–8 — These bits are used by the CPU when performing accesses using the direct
addressing mode. These register bits form bits [15:8] of the local address (see Figure 3-6).
Bit15
Bit8
Bit0
Bit7
DP [15:8]
CPU Address [15:0]
Figure 3-6. DIRECT Address Mapping
Example 3-1. This example demonstrates usage of the Direct Addressing Mode
3.3.2.3
MOVB
#$80,DIRECT
;Set DIRECT register to 0x80. Write once only.
;Global data accesses to the range 0xXX_80XX can be direct.
;Logical data accesses to the range 0x80XX are direct.
LDY
<$00
;Load the Y index register from 0x8000 (direct access).
;< operator forces direct access on some assemblers but in
;many cases assemblers are “direct page aware” and can
;automatically select direct mode.
Program Page Index Register (PPAGE)
Address: 0x0030
R
7
6
5
4
0
0
0
0
3
2
1
0
PIX3
PIX2
PIX1
PIX0
1
1
1
0
W
Reset
0
0
0
0
Figure 3-7. Program Page Index Register (PPAGE)
Read: Anytime
Write: Anytime
These four index bits are used to map 16KB blocks into the Flash page window located in the local (CPU
or BDM) memory map from address 0x8000 to address 0xBFFF (see Figure 3-8). This supports accessing
up to 256 KB of Flash (in the Global map) within the 64KB Local map. The PPAGE index register is
effectively used to construct paged Flash addresses in the Local map format. The CPU has special access
to read and write this register directly during execution of CALL and RTC instructions.
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Memory Map Control (S12PMMCV1)
Global Address [17:0]
Bit17
Bit0
Bit14 Bit13
PPAGE Register [3:0]
Address [13:0]
Address: CPU Local Address
or BDM Local Address
Figure 3-8. PPAGE Address Mapping
NOTE
Writes to this register using the special access of the CALL and RTC
instructions will be complete before the end of the instruction execution.
Table 3-7. PPAGE Field Descriptions
Field
Description
3–0
PIX[3:0]
Program Page Index Bits 3–0 — These page index bits are used to select which of the 256 P-Flash or ROM
array pages is to be accessed in the Program Page Window.
The fixed 16KB page from 0x0000 to 0x3FFF is the page number 0x0C. Parts of this page are covered by
Registers, D-Flash and RAM space. See SoC Guide for details.
The fixed 16KB page from 0x4000–0x7FFF is the page number 0x0D.
The reset value of 0x0E ensures that there is linear Flash space available between addresses 0x0000 and
0xFFFF out of reset.
The fixed 16KB page from 0xC000-0xFFFF is the page number 0x0F.
3.4
Functional Description
The S12PMMC block performs several basic functions of the S12I sub-system operation: MCU operation
modes, priority control, address mapping, select signal generation and access limitations for the system.
Each aspect is described in the following subsections.
3.4.1
•
•
MCU Operating Modes
Normal single chip mode
This is the operation mode for running application codeThere is no external bus in this mode.
Special single chip mode
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Memory Map Control (S12PMMCV1)
This mode is generally used for debugging operation, boot-strapping or security related
operations. The active background debug mode is in control of the CPU code execution and the
BDM firmware is waiting for serial commands sent through the BKGD pin.
3.4.2
3.4.2.1
Memory Map Scheme
CPU and BDM Memory Map Scheme
The BDM firmware lookup tables and BDM register memory locations share addresses with other
modules; however they are not visible in the memory map during user’s code execution. The BDM
memory resources are enabled only during the READ_BD and WRITE_BD access cycles to distinguish
between accesses to the BDM memory area and accesses to the other modules. (Refer to BDM Block
Guide for further details).
When the MCU enters active BDM mode, the BDM firmware lookup tables and the BDM registers
become visible in the local memory map in the range 0xFF00-0xFFFF (global address 0x3_FF00 0x3_FFFF) and the CPU begins execution of firmware commands or the BDM begins execution of
hardware commands. The resources which share memory space with the BDM module will not be visible
in the memory map during active BDM mode.
Please note that after the MCU enters active BDM mode the BDM firmware lookup tables and the BDM
registers will also be visible between addresses 0xBF00 and 0xBFFF if the PPAGE register contains value
of 0x0F.
3.4.2.1.1
Expansion of the Local Address Map
Expansion of the CPU Local Address Map
The program page index register in S12PMMC allows accessing up to 256KB of P-Flash in the global
memory map by using the four index bits (PPAGE[3:0]) to page 16x16 KB blocks into the program page
window located from address 0x8000 to address 0xBFFF in the local CPU memory map.
The page value for the program page window is stored in the PPAGE register. The value of the PPAGE
register can be read or written by normal memory accesses as well as by the CALL and RTC instructions
(see Section 3.6.1, “CALL and RTC Instructions).
Control registers, vector space and parts of the on-chip memories are located in unpaged portions of the
64KB local CPU address space.
The starting address of an interrupt service routine must be located in unpaged memory unless the user is
certain that the PPAGE register will be set to the appropriate value when the service routine is called.
However an interrupt service routine can call other routines that are in paged memory. The upper 16KB
block of the local CPU memory space (0xC000–0xFFFF) is unpaged. It is recommended that all reset and
interrupt vectors point to locations in this area or to the other unmapped pages sections of the local CPU
memory map.
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Expansion of the BDM Local Address Map
PPAGE and BDMPPR register is also used for the expansion of the BDM local address to the global
address. These registers can be read and written by the BDM.
The BDM expansion scheme is the same as the CPU expansion scheme.
The four BDMPPR Program Page index bits allow access to the full 256KB address map that can be
accessed with 18 address bits.
The BDM program page index register (BDMPPR) is used only when the feature is enabled in BDM and,
in the case the CPU is executing a firmware command which uses CPU instructions, or by a BDM
hardware commands. See the BDM Block Guide for further details. (see Figure 3-9).
BDM HARDWARE COMMAND
Global Address [17:0]
Bit17
Bit0
Bit14 Bit13
BDMPPR Register [3:0]
BDM Local Address [13:0]
BDM FIRMWARE COMMAND
Global Address [17:0]
Bit17
Bit0
Bit14 Bit13
BDMPPR Register [3:0]
CPU Local Address [13:0]
Figure 3-9. BDMPPR Address Mapping
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Memory Map Control (S12PMMCV1)
CPU and BDM
Local Memory Map
0x0000
Global Memory Map
0x0400
REGISTERS
0x1400
RAM_LOW
RAM
Unpaged P-Flash
0x0_4000
D-Flash
0x0_5400
NVM Resources
0x4000
(PPAGE 0x01)
RAMSIZE
RAM
NVM Resources
0x0_4400
RAMSIZE
Unimplemented Area
D-Flash
(PPAGE 0x00)
0x0_0000
REGISTERS
0x0_8000
P-Flash
10 *16K paged
0x8000
(PPAGE 0x02-0x0B))
Unpaged P-Flash
0x3_0000
P-Flash window
0 0 0 0 P3P2P1P0
Unpaged P-Flash
PPAGE
Unpaged P-Flash
Unpaged P-Flash
(PPAGE 0x0E)
Unpaged P-Flash
(PPAGE 0x0F)
0xC000
(PPAGE 0x0D)
0x3_4000
0x3_8000
Unpaged P-Flash
(PPAGE 0x0C)
Unpaged P-Flash
or
0x3_C000
0xFFFF
0x3_FFFF
Figure 3-10. Local to Global Address Mapping
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3.5
Implemented Memory in the System Memory Architecture
Each memory can be implemented in its maximum allowed size. But some devices have been defined for
smaller sizes, which means less implemented pages. All non implemented pages are called unimplemented
areas.
• Registers has a fixed size of 1KB, accessible via xbus0.
• SRAM has a maximum size of 11KB, accessible via xbus0.
• D-Flash has a fixed size of 4KB accessible via xbus0.
• P-Flash has a maximum size of 224KB, accessible via xbus0.
• NVM resources (IFR) including D-Flash have maximum size of 16KB (PPAGE 0x01).
3.5.0.1
Implemented Memory Map
The global memory spaces reserved for the internal resources (RAM, D-Flash, and P-Flash) are not
determined by the MMC module. Size of the individual internal resources are however fixed in the design
of the device cannot be changed by the user. Please refer to the SoC Guide for further details. Figure 3-11
and Table 3-8 show the memory spaces occupied by the on-chip resources. Please note that the memory
spaces have fixed top addresses.
Table 3-8. Global Implemented Memory Space
Internal Resource
Bottom Address
Top Address
Registers
0x0_0000
0x0_03FF
System RAM
RAM_LOW =
0x0_4000 minus RAMSIZE(1)
0x0_3FFF
D-Flash
0x0_4400
0x0_53FF
P-Flash
PF_LOW =
0x4_0000 minus FLASHSIZE(2)
1. RAMSIZE is the hexadecimal value of RAM SIZE in bytes
2. FLASHSIZE is the hexadecimal value of FLASH SIZE in bytes
0x3_FFFF
In single-chip modes accesses by the CPU12 (except for firmware commands) to any of the
unimplemented areas (see Figure 3-11) will result in an illegal access reset (system reset). BDM accesses
to the unimplemented areas are allowed but the data will be undefined.
No misaligned word access from the BDM module will occur; these accesses are blocked in the BDM
module (Refer to BDM Block Guide).
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Memory Map Control (S12PMMCV1)
CPU and BDM
Local Memory Map
0x0000
Global Memory Map
REGISTERS
D-Flash
REGISTERS
0x1400
RAM_LOW
Unpaged P-Flash
RAM
RAM
0x0_4400
NVM Resources
D-Flash
0x0_5400
NVM Resources
0x4000
(PPAGE 0x01)
RAMSIZE
0x0_4000
RAMSIZE
Unimplemented Area
(PPAGE 0x00)
0x0_0000
0x0400
0x0_8000
Unpaged P-Flash
Unimplemented area
0x8000
P-Flash window
0 0 0 0 P3P2P1P0
PPAGE
PF_LOW
0xC000
0xFFFF
PFSIZE
P-Flash
Unpaged P-Flash
0x3_FFFF
Figure 3-11. Implemented Global Address Mapping
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3.5.1
Chip Bus Control
The S12PMMC controls the address buses and the data buses that interface the bus masters (CPU12,
S12SBDM) with the rest of the system (master buses). In addition the MMC handles all CPU read data
bus swapping operations. All internal resources are connected to specific target buses (see Figure 3-12).
DBG
BDM
CPU
S12X1
S12X0
MMC “Crossbar Switch”
XBUS0
P-Flash
D-Flash
BDM
resources
SRAM
IPBI
Peripherals
Figure 3-12. S12I platform
3.5.1.1
Master Bus Prioritization regarding Access Conflicts on Target Buses
The arbitration scheme allows only one master to be connected to a target at any given time. The following
rules apply when prioritizing accesses from different masters to the same target bus:
• CPU12 always has priority over BDM.
• BDM has priority over CPU12 when its access is stalled for more than 128 cycles. In the later case
the CPU will be stalled after finishing the current operation and the BDM will gain access to the
bus.
3.5.2
Interrupts
The MMC does not generate any interrupts.
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3.6
3.6.1
Initialization/Application Information
CALL and RTC Instructions
CALL and RTC instructions are uninterruptable CPU instructions that automate page switching in the
program page window. The CALL instruction is similar to the JSR instruction, but the subroutine that is
called can be located anywhere in the local address space or in any Flash or ROM page visible through the
program page window. The CALL instruction calculates and stacks a return address, stacks the current
PPAGE value and writes a new instruction-supplied value to the PPAGE register. The PPAGE value
controls which of the 256 possible pages is visible through the 16 Kbyte program page window in the
64 Kbyte local CPU memory map. Execution then begins at the address of the called subroutine.
During the execution of the CALL instruction, the CPU performs the following steps:
1. Writes the current PPAGE value into an internal temporary register and writes the new instructionsupplied PPAGE value into the PPAGE register
2. Calculates the address of the next instruction after the CALL instruction (the return address) and
pushes this 16-bit value onto the stack
3. Pushes the temporarily stored PPAGE value onto the stack
4. Calculates the effective address of the subroutine, refills the queue and begins execution at the new
address
This sequence is uninterruptable. There is no need to inhibit interrupts during the CALL instruction
execution. A CALL instruction can be performed from any address to any other address in the local CPU
memory space.
The PPAGE value supplied by the instruction is part of the effective address of the CPU. For all addressing
mode variations (except indexed-indirect modes) the new page value is provided by an immediate operand
in the instruction. In indexed-indirect variations of the CALL instruction a pointer specifies memory
locations where the new page value and the address of the called subroutine are stored. Using indirect
addressing for both the new page value and the address within the page allows usage of values calculated
at run time rather than immediate values that must be known at the time of assembly.
The RTC instruction terminates subroutines invoked by a CALL instruction. The RTC instruction unstacks
the PPAGE value and the return address and refills the queue. Execution resumes with the next instruction
after the CALL instruction.
During the execution of an RTC instruction the CPU performs the following steps:
1. Pulls the previously stored PPAGE value from the stack
2. Pulls the 16-bit return address from the stack and loads it into the PC
3. Writes the PPAGE value into the PPAGE register
4. Refills the queue and resumes execution at the return address
This sequence is uninterruptable. The RTC can be executed from anywhere in the local CPU memory
space.
The CALL and RTC instructions behave like JSR and RTS instruction, they however require more
execution cycles. Usage of JSR/RTS instructions is therefore recommended when possible and
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CALL/RTC instructions should only be used when needed. The JSR and RTS instructions can be used to
access subroutines that are already present in the local CPU memory map (i.e. in the same page in the
program memory page window for example). However calling a function located in a different page
requires usage of the CALL instruction. The function must be terminated by the RTC instruction. Because
the RTC instruction restores contents of the PPAGE register from the stack, functions terminated with the
RTC instruction must be called using the CALL instruction even when the correct page is already present
in the memory map. This is to make sure that the correct PPAGE value will be present on stack at the time
of the RTC instruction execution.
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Memory Map Control (S12PMMCV1)
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Chapter 4
Interrupt Module (S12SINTV1)
Version
Number
Revision
Date
01.02
13 Sep
2007
updates for S12P family devices:
- re-added XIRQ and IRQ references since this functionality is used
on devices without D2D
- added low voltage reset as possible source to the pin reset vector
01.03
21 Nov
2007
added clarification of “Wake-up from STOP or WAIT by XIRQ with
X bit set” feature
01.04
20 May
2009
added footnote about availability of “Wake-up from STOP or WAIT
by XIRQ with X bit set” feature
4.1
Effective
Date
Author
Description of Changes
Introduction
The INT module decodes the priority of all system exception requests and provides the applicable vector
for processing the exception to the CPU. The INT module supports:
• I bit and X bit maskable interrupt requests
• A non-maskable unimplemented op-code trap
• A non-maskable software interrupt (SWI) or background debug mode request
• Three system reset vector requests
• A spurious interrupt vector
Each of the I bit maskable interrupt requests is assigned to a fixed priority level.
4.1.1
Glossary
Table 4-2 contains terms and abbreviations used in the document.
Table 4-2. Terminology
Term
CCR
Condition Code Register (in the CPU)
ISR
Interrupt Service Routine
MCU
4.1.2
•
•
Meaning
Micro-Controller Unit
Features
Interrupt vector base register (IVBR)
One spurious interrupt vector (at address vector base1 + 0x0080).
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•
•
•
•
•
•
•
•
4.1.3
•
•
•
•
4.1.4
2–58 I bit maskable interrupt vector requests (at addresses vector base + 0x0082–0x00F2).
I bit maskable interrupts can be nested.
One X bit maskable interrupt vector request (at address vector base + 0x00F4).
One non-maskable software interrupt request (SWI) or background debug mode vector request (at
address vector base + 0x00F6).
One non-maskable unimplemented op-code trap (TRAP) vector (at address vector base + 0x00F8).
Three system reset vectors (at addresses 0xFFFA–0xFFFE).
Determines the highest priority interrupt vector requests, drives the vector to the bus on CPU
request
Wakes up the system from stop or wait mode when an appropriate interrupt request occurs.
Modes of Operation
Run mode
This is the basic mode of operation.
Wait mode
In wait mode, the clock to the INT module is disabled. The INT module is however capable of
waking-up the CPU from wait mode if an interrupt occurs. Please refer to Section 4.5.3, “Wake Up
from Stop or Wait Mode” for details.
Stop Mode
In stop mode, the clock to the INT module is disabled. The INT module is however capable of
waking-up the CPU from stop mode if an interrupt occurs. Please refer to Section 4.5.3, “Wake Up
from Stop or Wait Mode” for details.
Freeze mode (BDM active)
In freeze mode (BDM active), the interrupt vector base register is overridden internally. Please
refer to Section 4.3.1.1, “Interrupt Vector Base Register (IVBR)” for details.
Block Diagram
Figure 4-1 shows a block diagram of the INT module.
1. The vector base is a 16-bit address which is accumulated from the contents of the interrupt vector base register (IVBR, used
as upper byte) and 0x00 (used as lower byte).
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Interrupt Module (S12SINTV1)
Peripheral
Interrupt Requests
Wake Up
CPU
Priority
Decoder
Non I bit Maskable Channels
To CPU
Vector
Address
IVBR
I bit Maskable Channels
Interrupt
Requests
Figure 4-1. INT Block Diagram
4.2
External Signal Description
The INT module has no external signals.
4.3
Memory Map and Register Definition
This section provides a detailed description of all registers accessible in the INT module.
4.3.1
Register Descriptions
This section describes in address order all the INT registers and their individual bits.
4.3.1.1
Interrupt Vector Base Register (IVBR)
Address: 0x0120
7
6
5
R
3
2
1
0
1
1
1
IVB_ADDR[7:0]
W
Reset
4
1
1
1
1
1
Figure 4-2. Interrupt Vector Base Register (IVBR)
Read: Anytime
Write: Anytime
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Table 4-3. IVBR Field Descriptions
Field
Description
7–0
Interrupt Vector Base Address Bits — These bits represent the upper byte of all vector addresses. Out of
IVB_ADDR[7:0] reset these bits are set to 0xFF (that means vectors are located at 0xFF80–0xFFFE) to ensure compatibility
to HCS12.
Note: A system reset will initialize the interrupt vector base register with “0xFF” before it is used to determine
the reset vector address. Therefore, changing the IVBR has no effect on the location of the three reset
vectors (0xFFFA–0xFFFE).
Note: If the BDM is active (that means the CPU is in the process of executing BDM firmware code), the
contents of IVBR are ignored and the upper byte of the vector address is fixed as “0xFF”. This is done
to enable handling of all non-maskable interrupts in the BDM firmware.
4.4
Functional Description
The INT module processes all exception requests to be serviced by the CPU module. These exceptions
include interrupt vector requests and reset vector requests. Each of these exception types and their overall
priority level is discussed in the subsections below.
4.4.1
S12S Exception Requests
The CPU handles both reset requests and interrupt requests. A priority decoder is used to evaluate the
priority of pending interrupt requests.
4.4.2
Interrupt Prioritization
The INT module contains a priority decoder to determine the priority for all interrupt requests pending for
the CPU. If more than one interrupt request is pending, the interrupt request with the higher vector address
wins the prioritization.
The following conditions must be met for an I bit maskable interrupt request to be processed.
1. The local interrupt enabled bit in the peripheral module must be set.
2. The I bit in the condition code register (CCR) of the CPU must be cleared.
3. There is no SWI, TRAP, or X bit maskable request pending.
NOTE
All non I bit maskable interrupt requests always have higher priority than
the I bit maskable interrupt requests. If the X bit in the CCR is cleared, it is
possible to interrupt an I bit maskable interrupt by an X bit maskable
interrupt. It is possible to nest non maskable interrupt requests, for example
by nesting SWI or TRAP calls.
Since an interrupt vector is only supplied at the time when the CPU requests it, it is possible that a higher
priority interrupt request could override the original interrupt request that caused the CPU to request the
vector. In this case, the CPU will receive the highest priority vector and the system will process this
interrupt request first, before the original interrupt request is processed.
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If the interrupt source is unknown (for example, in the case where an interrupt request becomes inactive
after the interrupt has been recognized, but prior to the CPU vector request), the vector address supplied
to the CPU will default to that of the spurious interrupt vector.
NOTE
Care must be taken to ensure that all interrupt requests remain active until
the system begins execution of the applicable service routine; otherwise, the
exception request may not get processed at all or the result may be a
spurious interrupt request (vector at address (vector base + 0x0080)).
4.4.3
Reset Exception Requests
The INT module supports three system reset exception request types (please refer to the Clock and Reset
generator module for details):
1. Pin reset, power-on reset or illegal address reset, low voltage reset (if applicable)
2. Clock monitor reset request
3. COP watchdog reset request
4.4.4
Exception Priority
The priority (from highest to lowest) and address of all exception vectors issued by the INT module upon
request by the CPU is shown in Table 4-4.
Table 4-4. Exception Vector Map and Priority
Vector Address(1)
Source
0xFFFE
Pin reset, power-on reset, illegal address reset, low voltage reset (if applicable)
0xFFFC
Clock monitor reset
0xFFFA
COP watchdog reset
(Vector base + 0x00F8)
Unimplemented opcode trap
(Vector base + 0x00F6)
Software interrupt instruction (SWI) or BDM vector request
(Vector base + 0x00F4)
X bit maskable interrupt request (XIRQ or D2D error interrupt)(2)
(Vector base + 0x00F2)
IRQ or D2D interrupt request(3)
(Vector base + 0x00F0–0x0082) Device specific I bit maskable interrupt sources (priority determined by the low byte of the
vector address, in descending order)
(Vector base + 0x0080)
Spurious interrupt
1. 16 bits vector address based
2. D2D error interrupt on MCUs featuring a D2D initiator module, otherwise XIRQ pin interrupt
3. D2D interrupt on MCUs featuring a D2D initiator module, otherwise IRQ pin interrupt
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4.5
4.5.1
Initialization/Application Information
Initialization
After system reset, software should:
1. Initialize the interrupt vector base register if the interrupt vector table is not located at the default
location (0xFF80–0xFFF9).
2. Enable I bit maskable interrupts by clearing the I bit in the CCR.
3. Enable the X bit maskable interrupt by clearing the X bit in the CCR.
4.5.2
Interrupt Nesting
The interrupt request scheme makes it possible to nest I bit maskable interrupt requests handled by the
CPU.
• I bit maskable interrupt requests can be interrupted by an interrupt request with a higher priority.
I bit maskable interrupt requests cannot be interrupted by other I bit maskable interrupt requests per
default. In order to make an interrupt service routine (ISR) interruptible, the ISR must explicitly clear the
I bit in the CCR (CLI). After clearing the I bit, other I bit maskable interrupt requests can interrupt the
current ISR.
An ISR of an interruptible I bit maskable interrupt request could basically look like this:
1. Service interrupt, that is clear interrupt flags, copy data, etc.
2. Clear I bit in the CCR by executing the instruction CLI (thus allowing other I bit maskable interrupt
requests)
3. Process data
4. Return from interrupt by executing the instruction RTI
4.5.3
4.5.3.1
Wake Up from Stop or Wait Mode
CPU Wake Up from Stop or Wait Mode
Every I bit maskable interrupt request is capable of waking the MCU from stop or wait mode. To determine
whether an I bit maskable interrupts is qualified to wake-up the CPU or not, the same conditions as in
normal run mode are applied during stop or wait mode:
• If the I bit in the CCR is set, all I bit maskable interrupts are masked from waking-up the MCU.
Since there are no clocks running in stop mode, only interrupts which can be asserted asynchronously can
wake-up the MCU from stop mode.
The X bit maskable interrupt request can wake up the MCU from stop or wait mode at anytime, even if the
X bit in CCR is set1.
1. The capability of the XIRQ pin to wake-up the MCU with the X bit set may not be available if, for example, the XIRQ pin is
shared with other peripheral modules on the device. Please refer to the Device section of the MCU reference manual for details.
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If the X bit maskable interrupt request is used to wake-up the MCU with the X bit in the CCR set, the
associated ISR is not called. The CPU then resumes program execution with the instruction following the
WAI or STOP instruction. This features works following the same rules like any interrupt request, that is
care must be taken that the X interrupt request used for wake-up remains active at least until the system
begins execution of the instruction following the WAI or STOP instruction; otherwise, wake-up may not
occur.
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Chapter 5
Background Debug Module (S12SBDMV1)
Revision History
5.1
Revision Number
Date
s12s_bdm.01.00.00
08.Feb.2006
General
First version of S12SBDMV1
Summary of Changes
s12s_bdm.01.00.02
09.Feb.2006
General
Updated register address information & Block Version
s12s_bdm.01.00.12
10.May.2006
5.3.2/5-134
s12s_bdm.01.01.01
20.Sep.2007
General
Added conditional text for S12P family
1.02
08.Apr.2009
General
Minor text corrections following review
1.03
14.May.2009
Internal Conditional text only
1.04
30.Nov.2009
Internal Conditional text only
Removed CLKSW bit and description
Introduction
This section describes the functionality of the background debug module (BDM) sub-block of the HCS12S
core platform.
The background debug module (BDM) sub-block is a single-wire, background debug system implemented
in on-chip hardware for minimal CPU intervention. All interfacing with the BDM is done via the BKGD
pin.
The BDM has enhanced capability for maintaining synchronization between the target and host while
allowing more flexibility in clock rates. This includes a sync signal to determine the communication rate
and a handshake signal to indicate when an operation is complete. The system is backwards compatible to
the BDM of the S12 family with the following exceptions:
• TAGGO command not supported by S12SBDM
• External instruction tagging feature is part of the DBG module
• S12SBDM register map and register content modified
• Family ID readable from BDM ROM at global address 0x3_FF0F in active BDM
(value for devices with HCS12S core is 0xC2)
• Clock switch removed from BDM (CLKSW bit removed from BDMSTS register)
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Background Debug Module (S12SBDMV1)
5.1.1
Features
The BDM includes these distinctive features:
• Single-wire communication with host development system
• Enhanced capability for allowing more flexibility in clock rates
• SYNC command to determine communication rate
• GO_UNTIL command
• Hardware handshake protocol to increase the performance of the serial communication
• Active out of reset in special single chip mode
• Nine hardware commands using free cycles, if available, for minimal CPU intervention
• Hardware commands not requiring active BDM
• 14 firmware commands execute from the standard BDM firmware lookup table
• Software control of BDM operation during wait mode
• When secured, hardware commands are allowed to access the register space in special single chip
mode, if the Flash erase tests fail.
• Family ID readable from BDM ROM at global address 0x3_FF0F in active BDM
(value for devices with HCS12S core is 0xC2)
• BDM hardware commands are operational until system stop mode is entered
5.1.2
Modes of Operation
BDM is available in all operating modes but must be enabled before firmware commands are executed.
Some systems may have a control bit that allows suspending the function during background debug mode.
5.1.2.1
Regular Run Modes
All of these operations refer to the part in run mode and not being secured. The BDM does not provide
controls to conserve power during run mode.
• Normal modes
General operation of the BDM is available and operates the same in all normal modes.
• Special single chip mode
In special single chip mode, background operation is enabled and active out of reset. This allows
programming a system with blank memory.
5.1.2.2
Secure Mode Operation
If the device is in secure mode, the operation of the BDM is reduced to a small subset of its regular run
mode operation. Secure operation prevents access to Flash other than allowing erasure. For more
information please see Section 5.4.1, “Security”.
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5.1.2.3
Low-Power Modes
The BDM can be used until stop mode is entered. When CPU is in wait mode all BDM firmware
commands as well as the hardware BACKGROUND command cannot be used and are ignored. In this case
the CPU can not enter BDM active mode, and only hardware read and write commands are available. Also
the CPU can not enter a low power mode (stop or wait) during BDM active mode.
In stop mode the BDM clocks are stopped. When BDM clocks are disabled and stop mode is exited, the
BDM clocks will restart and BDM will have a soft reset (clearing the instruction register, any command in
progress and disable the ACK function). The BDM is now ready to receive a new command.
5.1.3
Block Diagram
A block diagram of the BDM is shown in Figure 5-1.
Host
System
BKGD
Serial
Interface
Data
16-Bit Shift Register
Control
Register Block
Address
TRACE
BDMACT
Instruction Code
and
Execution
Bus Interface
and
Control Logic
Data
Control
Clocks
ENBDM
SDV
Standard BDM Firmware
LOOKUP TABLE
UNSEC
Secured BDM Firmware
LOOKUP TABLE
BDMSTS
Register
Figure 5-1. BDM Block Diagram
5.2
External Signal Description
A single-wire interface pin called the background debug interface (BKGD) pin is used to communicate
with the BDM system. During reset, this pin is a mode select input which selects between normal and
special modes of operation. After reset, this pin becomes the dedicated serial interface pin for the
background debug mode. The communication rate of this pin is based on the settings for the VCO clock
(CPMUSYNR). The BDM clock frequency is always VCO clock frequency divided by 8. After reset the
BDM clock is based on the reset values of the CPMUSYNR register (4 MHz). When modifying the VCO
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Background Debug Module (S12SBDMV1)
clock please make sure that the communication rate is adapted accordingly and a communication time-out
(BDM soft reset) has occurred.
5.3
Memory Map and Register Definition
5.3.1
Module Memory Map
Table 5-1 shows the BDM memory map when BDM is active.
Table 5-1. BDM Memory Map
5.3.2
Global Address
Module
Size
(Bytes)
0x3_FF00–0x3_FF0B
BDM registers
12
0x3_FF0C–0x3_FF0E
BDM firmware ROM
3
0x3_FF0F
Family ID (part of BDM firmware ROM)
1
0x3_FF10–0x3_FFFF
BDM firmware ROM
240
Register Descriptions
A summary of the registers associated with the BDM is shown in Figure 5-2. Registers are accessed by
host-driven communications to the BDM hardware using READ_BD and WRITE_BD commands.
Global
Address
Register
Name
0x3_FF00
Reserved
R
Bit 7
6
5
4
3
2
1
Bit 0
X
X
X
X
X
X
0
0
BDMACT
0
SDV
TRACE
0
UNSEC
0
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
W
0x3_FF01
BDMSTS
R
W
0x3_FF02
Reserved
R
ENBDM
W
0x3_FF03
Reserved
R
W
0x3_FF04
Reserved
R
W
= Unimplemented, Reserved
X
= Indeterminate
= Implemented (do not alter)
0
= Always read zero
Figure 5-2. BDM Register Summary
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Global
Address
Register
Name
0x3_FF05
Reserved
Bit 7
6
5
4
3
2
1
Bit 0
X
X
X
X
X
X
X
X
CCR7
CCR6
CCR5
CCR4
CCR3
CCR2
CCR1
CCR0
0
0
0
0
0
0
0
0
0
0
0
BPP3
BPP2
BPP1
BPP0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
R
W
0x3_FF06
BDMCCR
R
W
0x3_FF07
Reserved
R
W
0x3_FF08
BDMPPR
R
W
0x3_FF09
Reserved
BPAE
R
W
0x3_FF0A
Reserved
R
W
0x3_FF0B
Reserved
R
W
= Unimplemented, Reserved
= Indeterminate
X
= Implemented (do not alter)
= Always read zero
0
Figure 5-2. BDM Register Summary (continued)
5.3.2.1
BDM Status Register (BDMSTS)
Register Global Address 0x3_FF01
7
R
W
ENBDM
6
5
4
3
2
1
0
BDMACT
0
SDV
TRACE
0
UNSEC
0
1
0
0
0
0
0(2)
0
0
0
0
0
0
0
0
Reset
Special Single-Chip Mode
All Other Modes
0(1)
0
= Unimplemented, Reserved
= Implemented (do not alter)
0
= Always read zero
1. ENBDM is read as 1 by a debugging environment in special single chip mode when the device is not secured or secured but
fully erased (Flash). This is because the ENBDM bit is set by the standard BDM firmware before a BDM command can be fully
transmitted and executed.
2. UNSEC is read as 1 by a debugging environment in special single chip mode when the device is secured and fully erased,
else it is 0 and can only be read if not secure (see also bit description).
Figure 5-3. BDM Status Register (BDMSTS)
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Read: All modes through BDM operation when not secured
Write: All modes through BDM operation when not secured, but subject to the following:
— ENBDM should only be set via a BDM hardware command if the BDM firmware commands
are needed. (This does not apply in special single chip mode).
— BDMACT can only be set by BDM hardware upon entry into BDM. It can only be cleared by
the standard BDM firmware lookup table upon exit from BDM active mode.
— All other bits, while writable via BDM hardware or standard BDM firmware write commands,
should only be altered by the BDM hardware or standard firmware lookup table as part of BDM
command execution.
Table 5-2. BDMSTS Field Descriptions
Field
Description
7
ENBDM
Enable BDM — This bit controls whether the BDM is enabled or disabled. When enabled, BDM can be made
active to allow firmware commands to be executed. When disabled, BDM cannot be made active but BDM
hardware commands are still allowed.
0 BDM disabled
1 BDM enabled
Note: ENBDM is set out of reset in special single chip mode. In special single chip mode with the device
secured, this bit will not be set until after the Flash erase verify tests are complete.
6
BDMACT
BDM Active Status — This bit becomes set upon entering BDM. The standard BDM firmware lookup table is
then enabled and put into the memory map. BDMACT is cleared by a carefully timed store instruction in the
standard BDM firmware as part of the exit sequence to return to user code and remove the BDM memory from
the map.
0 BDM not active
1 BDM active
4
SDV
Shift Data Valid — This bit is set and cleared by the BDM hardware. It is set after data has been transmitted as
part of a BDM firmware or hardware read command or after data has been received as part of a BDM firmware
or hardware write command. It is cleared when the next BDM command has been received or BDM is exited.
SDV is used by the standard BDM firmware to control program flow execution.
0 Data phase of command not complete
1 Data phase of command is complete
3
TRACE
TRACE1 BDM Firmware Command is Being Executed — This bit gets set when a BDM TRACE1 firmware
command is first recognized. It will stay set until BDM firmware is exited by one of the following BDM commands:
GO or GO_UNTIL.
0 TRACE1 command is not being executed
1 TRACE1 command is being executed
1
UNSEC
Unsecure — If the device is secured this bit is only writable in special single chip mode from the BDM secure
firmware. It is in a zero state as secure mode is entered so that the secure BDM firmware lookup table is enabled
and put into the memory map overlapping the standard BDM firmware lookup table.
The secure BDM firmware lookup table verifies that the on-chip Flash is erased. This being the case, the UNSEC
bit is set and the BDM program jumps to the start of the standard BDM firmware lookup table and the secure
BDM firmware lookup table is turned off. If the erase test fails, the UNSEC bit will not be asserted.
0 System is in a secured mode.
1 System is in a unsecured mode.
Note: When UNSEC is set, security is off and the user can change the state of the secure bits in the on-chip
Flash EEPROM. Note that if the user does not change the state of the bits to “unsecured” mode, the
system will be secured again when it is next taken out of reset.After reset this bit has no meaning or effect
when the security byte in the Flash EEPROM is configured for unsecure mode.
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Background Debug Module (S12SBDMV1)
Register Global Address 0x3_FF06
7
6
5
4
3
2
1
0
CCR7
CCR6
CCR5
CCR4
CCR3
CCR2
CCR1
CCR0
Special Single-Chip Mode
1
1
0
0
1
0
0
0
All Other Modes
0
0
0
0
0
0
0
0
R
W
Reset
Figure 5-4. BDM CCR Holding Register (BDMCCR)
Read: All modes through BDM operation when not secured
Write: All modes through BDM operation when not secured
NOTE
When BDM is made active, the CPU stores the content of its CCR register
in the BDMCCR register. However, out of special single-chip reset, the
BDMCCR is set to 0xD8 and not 0xD0 which is the reset value of the CCR
register in this CPU mode. Out of reset in all other modes the BDMCCR
register is read zero.
When entering background debug mode, the BDM CCR holding register is used to save the condition code
register of the user’s program. It is also used for temporary storage in the standard BDM firmware mode.
The BDM CCR holding register can be written to modify the CCR value.
5.3.2.2
BDM Program Page Index Register (BDMPPR)
Register Global Address 0x3_FF08
7
R
W
Reset
BPAE
0
6
5
4
0
0
0
0
0
0
3
2
1
0
BPP3
BPP2
BPP1
BPP0
0
0
0
0
= Unimplemented, Reserved
Figure 5-5. BDM Program Page Register (BDMPPR)
Read: All modes through BDM operation when not secured
Write: All modes through BDM operation when not secured
Table 5-3. BDMPPR Field Descriptions
Field
Description
7
BPAE
BDM Program Page Access Enable Bit — BPAE enables program page access for BDM hardware and
firmware read/write instructions The BDM hardware commands used to access the BDM registers (READ_BD
and WRITE_BD) can not be used for global accesses even if the BGAE bit is set.
0 BDM Program Paging disabled
1 BDM Program Paging enabled
3–0
BPP[3:0]
BDM Program Page Index Bits 3–0 — These bits define the selected program page. For more detailed
information regarding the program page window scheme, please refer to the S12S_MMC Block Guide.
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5.3.3
Family ID Assignment
The family ID is an 8-bit value located in the BDM ROM in active BDM (at global address: 0x3_FF0F).
The read-only value is a unique family ID which is 0xC2 for devices with an HCS12S core.
5.4
Functional Description
The BDM receives and executes commands from a host via a single wire serial interface. There are two
types of BDM commands: hardware and firmware commands.
Hardware commands are used to read and write target system memory locations and to enter active
background debug mode, see Section 5.4.3, “BDM Hardware Commands”. Target system memory
includes all memory that is accessible by the CPU.
Firmware commands are used to read and write CPU resources and to exit from active background debug
mode, see Section 5.4.4, “Standard BDM Firmware Commands”. The CPU resources referred to are the
accumulator (D), X index register (X), Y index register (Y), stack pointer (SP), and program counter (PC).
Hardware commands can be executed at any time and in any mode excluding a few exceptions as
highlighted (see Section 5.4.3, “BDM Hardware Commands”) and in secure mode (see Section 5.4.1,
“Security”). BDM firmware commands can only be executed when the system is not secure and is in active
background debug mode (BDM).
5.4.1
Security
If the user resets into special single chip mode with the system secured, a secured mode BDM firmware
lookup table is brought into the map overlapping a portion of the standard BDM firmware lookup table.
The secure BDM firmware verifies that the on-chip Flash EEPROM are erased. This being the case, the
UNSEC and ENBDM bit will get set. The BDM program jumps to the start of the standard BDM firmware
and the secured mode BDM firmware is turned off and all BDM commands are allowed. If the Flash does
not verify as erased, the BDM firmware sets the ENBDM bit, without asserting UNSEC, and the firmware
enters a loop. This causes the BDM hardware commands to become enabled, but does not enable the
firmware commands. This allows the BDM hardware to be used to erase the Flash.
BDM operation is not possible in any other mode than special single chip mode when the device is secured.
The device can only be unsecured via BDM serial interface in special single chip mode. For more
information regarding security, please see the S12S_9SEC Block Guide.
5.4.2
Enabling and Activating BDM
The system must be in active BDM to execute standard BDM firmware commands. BDM can be activated
only after being enabled. BDM is enabled by setting the ENBDM bit in the BDM status (BDMSTS)
register. The ENBDM bit is set by writing to the BDM status (BDMSTS) register, via the single-wire
interface, using a hardware command such as WRITE_BD_BYTE.
After being enabled, BDM is activated by one of the following1:
• Hardware BACKGROUND command
1. BDM is enabled and active immediately out of special single-chip reset.
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•
•
CPU BGND instruction
Breakpoint force or tag mechanism1
When BDM is activated, the CPU finishes executing the current instruction and then begins executing the
firmware in the standard BDM firmware lookup table. When BDM is activated by a breakpoint, the type
of breakpoint used determines if BDM becomes active before or after execution of the next instruction.
NOTE
If an attempt is made to activate BDM before being enabled, the CPU
resumes normal instruction execution after a brief delay. If BDM is not
enabled, any hardware BACKGROUND commands issued are ignored by
the BDM and the CPU is not delayed.
In active BDM, the BDM registers and standard BDM firmware lookup table are mapped to addresses
0x3_FF00 to 0x3_FFFF. BDM registers are mapped to addresses 0x3_FF00 to 0x3_FF0B. The BDM uses
these registers which are readable anytime by the BDM. However, these registers are not readable by user
programs.
When BDM is activated while CPU executes code overlapping with BDM firmware space the saved
program counter (PC) will be auto incremented by one from the BDM firmware, no matter what caused
the entry into BDM active mode (BGND instruction, BACKGROUND command or breakpoints). In such
a case the PC must be set to the next valid address via a WRITE_PC command before executing the GO
command.
5.4.3
BDM Hardware Commands
Hardware commands are used to read and write target system memory locations and to enter active
background debug mode. Target system memory includes all memory that is accessible by the CPU such
as on-chip RAM, Flash, I/O and control registers.
Hardware commands are executed with minimal or no CPU intervention and do not require the system to
be in active BDM for execution, although, they can still be executed in this mode. When executing a
hardware command, the BDM sub-block waits for a free bus cycle so that the background access does not
disturb the running application program. If a free cycle is not found within 128 clock cycles, the CPU is
momentarily frozen so that the BDM can steal a cycle. When the BDM finds a free cycle, the operation
does not intrude on normal CPU operation provided that it can be completed in a single cycle. However,
if an operation requires multiple cycles the CPU is frozen until the operation is complete, even though the
BDM found a free cycle.
The BDM hardware commands are listed in Table 5-4.
The READ_BD and WRITE_BD commands allow access to the BDM register locations. These locations
are not normally in the system memory map but share addresses with the application in memory. To
distinguish between physical memory locations that share the same address, BDM memory resources are
1. This method is provided by the S12S_DBG module.
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enabled just for the READ_BD and WRITE_BD access cycle. This allows the BDM to access BDM
locations unobtrusively, even if the addresses conflict with the application memory map.
Table 5-4. Hardware Commands
Opcode
(hex)
Data
Description
BACKGROUND
90
None
Enter background mode if BDM is enabled. If enabled, an ACK will be issued
when the part enters active background mode.
ACK_ENABLE
D5
None
Enable Handshake. Issues an ACK pulse after the command is executed.
ACK_DISABLE
D6
None
Disable Handshake. This command does not issue an ACK pulse.
READ_BD_BYTE
E4
16-bit address Read from memory with standard BDM firmware lookup table in map.
16-bit data out Odd address data on low byte; even address data on high byte.
READ_BD_WORD
EC
16-bit address Read from memory with standard BDM firmware lookup table in map.
16-bit data out Must be aligned access.
READ_BYTE
E0
16-bit address Read from memory with standard BDM firmware lookup table out of map.
16-bit data out Odd address data on low byte; even address data on high byte.
READ_WORD
E8
16-bit address Read from memory with standard BDM firmware lookup table out of map.
16-bit data out Must be aligned access.
WRITE_BD_BYTE
C4
16-bit address Write to memory with standard BDM firmware lookup table in map.
16-bit data in Odd address data on low byte; even address data on high byte.
WRITE_BD_WORD
CC
16-bit address Write to memory with standard BDM firmware lookup table in map.
16-bit data in Must be aligned access.
WRITE_BYTE
C0
16-bit address Write to memory with standard BDM firmware lookup table out of map.
16-bit data in Odd address data on low byte; even address data on high byte.
WRITE_WORD
C8
16-bit address Write to memory with standard BDM firmware lookup table out of map.
16-bit data in Must be aligned access.
Command
NOTE:
If enabled, ACK will occur when data is ready for transmission for all BDM READ commands and will occur after the write is
complete for all BDM WRITE commands.
5.4.4
Standard BDM Firmware Commands
BDM firmware commands are used to access and manipulate CPU resources. The system must be in active
BDM to execute standard BDM firmware commands, see Section 5.4.2, “Enabling and Activating BDM”.
Normal instruction execution is suspended while the CPU executes the firmware located in the standard
BDM firmware lookup table. The hardware command BACKGROUND is the usual way to activate BDM.
As the system enters active BDM, the standard BDM firmware lookup table and BDM registers become
visible in the on-chip memory map at 0x3_FF00–0x3_FFFF, and the CPU begins executing the standard
BDM firmware. The standard BDM firmware watches for serial commands and executes them as they are
received.
The firmware commands are shown in Table 5-5.
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Table 5-5. Firmware Commands
Command(1)
Opcode
(hex)
Data
Description
READ_NEXT(2)
62
16-bit data out Increment X index register by 2 (X = X + 2), then read word X points to.
READ_PC
63
16-bit data out Read program counter.
READ_D
64
16-bit data out Read D accumulator.
READ_X
65
16-bit data out Read X index register.
READ_Y
66
16-bit data out Read Y index register.
READ_SP
67
16-bit data out Read stack pointer.
WRITE_NEXT
42
16-bit data in
Increment X index register by 2 (X = X + 2), then write word to location
pointed to by X.
WRITE_PC
43
16-bit data in
Write program counter.
WRITE_D
44
16-bit data in
Write D accumulator.
WRITE_X
45
16-bit data in
Write X index register.
WRITE_Y
46
16-bit data in
Write Y index register.
WRITE_SP
47
16-bit data in
Write stack pointer.
GO
08
none
Go to user program. If enabled, ACK will occur when leaving active
background mode.
GO_UNTIL(3)
0C
none
Go to user program. If enabled, ACK will occur upon returning to active
background mode.
TRACE1
10
none
Execute one user instruction then return to active BDM. If enabled,
ACK will occur upon returning to active background mode.
TAGGO -> GO
18
none
(Previous enable tagging and go to user program.)
This command will be deprecated and should not be used anymore.
Opcode will be executed as a GO command.
1. If enabled, ACK will occur when data is ready for transmission for all BDM READ commands and will occur after the write is
complete for all BDM WRITE commands.
2. When the firmware command READ_NEXT or WRITE_NEXT is used to access the BDM address space the BDM resources
are accessed rather than user code. Writing BDM firmware is not possible.
3. System stop disables the ACK function and ignored commands will not have an ACK-pulse (e.g., CPU in stop or wait mode).
The GO_UNTIL command will not get an Acknowledge if CPU executes the wait or stop instruction before the “UNTIL”
condition (BDM active again) is reached (see Section 5.4.7, “Serial Interface Hardware Handshake Protocol” last note).
5.4.5
BDM Command Structure
Hardware and firmware BDM commands start with an 8-bit opcode followed by a 16-bit address and/or a
16-bit data word, depending on the command. All the read commands return 16 bits of data despite the
byte or word implication in the command name.
8-bit reads return 16-bits of data, only one byte of which contains valid data.
If reading an even address, the valid data will appear in the MSB. If reading
an odd address, the valid data will appear in the LSB.
16-bit misaligned reads and writes are generally not allowed. If attempted
by BDM hardware command, the BDM ignores the least significant bit of
the address and assumes an even address from the remaining bits.
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For hardware data read commands, the external host must wait at least 150 bus clock cycles after sending
the address before attempting to obtain the read data. This is to be certain that valid data is available in the
BDM shift register, ready to be shifted out. For hardware write commands, the external host must wait
150 bus clock cycles after sending the data to be written before attempting to send a new command. This
is to avoid disturbing the BDM shift register before the write has been completed. The 150 bus clock cycle
delay in both cases includes the maximum 128 cycle delay that can be incurred as the BDM waits for a
free cycle before stealing a cycle.
For BDM firmware read commands, the external host should wait at least 48 bus clock cycles after sending
the command opcode and before attempting to obtain the read data. The 48 cycle wait allows enough time
for the requested data to be made available in the BDM shift register, ready to be shifted out.
For BDM firmware write commands, the external host must wait 36 bus clock cycles after sending the data
to be written before attempting to send a new command. This is to avoid disturbing the BDM shift register
before the write has been completed.
The external host should wait for at least for 76 bus clock cycles after a TRACE1 or GO command before
starting any new serial command. This is to allow the CPU to exit gracefully from the standard BDM
firmware lookup table and resume execution of the user code. Disturbing the BDM shift register
prematurely may adversely affect the exit from the standard BDM firmware lookup table.
NOTE
If the bus rate of the target processor is unknown or could be changing, it is
recommended that the ACK (acknowledge function) is used to indicate
when an operation is complete. When using ACK, the delay times are
automated.
Figure 5-6 represents the BDM command structure. The command blocks illustrate a series of eight bit
times starting with a falling edge. The bar across the top of the blocks indicates that the BKGD line idles
in the high state. The time for an 8-bit command is 8 × 16 target clock cycles.1
1. Target clock cycles are cycles measured using the target MCU’s serial clock rate. See Section 5.4.6, “BDM Serial Interface”
and Section 5.3.2.1, “BDM Status Register (BDMSTS)” for information on how serial clock rate is selected.
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Hardware
Read
8 Bits
AT ~16 TC/Bit
16 Bits
AT ~16 TC/Bit
Command
Address
150-BC
Delay
16 Bits
AT ~16 TC/Bit
Data
Next
Command
150-BC
Delay
Hardware
Write
Command
Address
Data
Next
Command
48-BC
DELAY
Firmware
Read
Command
Next
Command
Data
36-BC
DELAY
Firmware
Write
Command
Data
Next
Command
76-BC
Delay
GO,
TRACE
Command
Next
Command
BC = Bus Clock Cycles
TC = Target Clock Cycles
Figure 5-6. BDM Command Structure
5.4.6
BDM Serial Interface
The BDM communicates with external devices serially via the BKGD pin. During reset, this pin is a mode
select input which selects between normal and special modes of operation. After reset, this pin becomes
the dedicated serial interface pin for the BDM.
The BDM serial interface is timed based on the VCO clock (please refer to the CPMU Block Guide for
more details), which gets divided by 8. This clock will be referred to as the target clock in the following
explanation.
The BDM serial interface uses a clocking scheme in which the external host generates a falling edge on
the BKGD pin to indicate the start of each bit time. This falling edge is sent for every bit whether data is
transmitted or received. Data is transferred most significant bit (MSB) first at 16 target clock cycles per
bit. The interface times out if 512 clock cycles occur between falling edges from the host.
The BKGD pin is a pseudo open-drain pin and has an weak on-chip active pull-up that is enabled at all
times. It is assumed that there is an external pull-up and that drivers connected to BKGD do not typically
drive the high level. Since R-C rise time could be unacceptably long, the target system and host provide
brief driven-high (speedup) pulses to drive BKGD to a logic 1. The source of this speedup pulse is the host
for transmit cases and the target for receive cases.
The timing for host-to-target is shown in Figure 5-7 and that of target-to-host in Figure 5-8 and
Figure 5-9. All four cases begin when the host drives the BKGD pin low to generate a falling edge. Since
the host and target are operating from separate clocks, it can take the target system up to one full clock
cycle to recognize this edge. The target measures delays from this perceived start of the bit time while the
host measures delays from the point it actually drove BKGD low to start the bit up to one target clock cycle
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earlier. Synchronization between the host and target is established in this manner at the start of every bit
time.
Figure 5-7 shows an external host transmitting a logic 1 and transmitting a logic 0 to the BKGD pin of a
target system. The host is asynchronous to the target, so there is up to a one clock-cycle delay from the
host-generated falling edge to where the target recognizes this edge as the beginning of the bit time. Ten
target clock cycles later, the target senses the bit level on the BKGD pin. Internal glitch detect logic
requires the pin be driven high no later that eight target clock cycles after the falling edge for a logic 1
transmission.
Since the host drives the high speedup pulses in these two cases, the rising edges look like digitally driven
signals.
BDM Clock
(Target MCU)
Host
Transmit 1
Host
Transmit 0
Perceived
Start of Bit Time
Target Senses Bit
10 Cycles
Synchronization
Uncertainty
Earliest
Start of
Next Bit
Figure 5-7. BDM Host-to-Target Serial Bit Timing
The receive cases are more complicated. Figure 5-8 shows the host receiving a logic 1 from the target
system. Since the host is asynchronous to the target, there is up to one clock-cycle delay from the hostgenerated falling edge on BKGD to the perceived start of the bit time in the target. The host holds the
BKGD pin low long enough for the target to recognize it (at least two target clock cycles). The host must
release the low drive before the target drives a brief high speedup pulse seven target clock cycles after the
perceived start of the bit time. The host should sample the bit level about 10 target clock cycles after it
started the bit time.
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BDM Clock
(Target MCU)
Host
Drive to
BKGD Pin
Target System
Speedup
Pulse
High-Impedance
High-Impedance
High-Impedance
Perceived
Start of Bit Time
R-C Rise
BKGD Pin
10 Cycles
10 Cycles
Host Samples
BKGD Pin
Earliest
Start of
Next Bit
Figure 5-8. BDM Target-to-Host Serial Bit Timing (Logic 1)
Figure 5-9 shows the host receiving a logic 0 from the target. Since the host is asynchronous to the target,
there is up to a one clock-cycle delay from the host-generated falling edge on BKGD to the start of the bit
time as perceived by the target. The host initiates the bit time but the target finishes it. Since the target
wants the host to receive a logic 0, it drives the BKGD pin low for 13 target clock cycles then briefly drives
it high to speed up the rising edge. The host samples the bit level about 10 target clock cycles after starting
the bit time.
BDM Clock
(Target MCU)
Host
Drive to
BKGD Pin
High-Impedance
Speedup Pulse
Target System
Drive and
Speedup Pulse
Perceived
Start of Bit Time
BKGD Pin
10 Cycles
10 Cycles
Host Samples
BKGD Pin
Earliest
Start of
Next Bit
Figure 5-9. BDM Target-to-Host Serial Bit Timing (Logic 0)
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5.4.7
Serial Interface Hardware Handshake Protocol
BDM commands that require CPU execution are ultimately treated at the MCU bus rate. Since the BDM
clock source can be modified when changing the settings for the VCO frequency (CPMUSYNR), it is very
helpful to provide a handshake protocol in which the host could determine when an issued command is
executed by the CPU. The BDM clock frequency is always VCO frequency divided by 8. The alternative
is to always wait the amount of time equal to the appropriate number of cycles at the slowest possible rate
the clock could be running. This sub-section will describe the hardware handshake protocol.
The hardware handshake protocol signals to the host controller when an issued command was successfully
executed by the target. This protocol is implemented by a 16 serial clock cycle low pulse followed by a
brief speedup pulse in the BKGD pin. This pulse is generated by the target MCU when a command, issued
by the host, has been successfully executed (see Figure 5-10). This pulse is referred to as the ACK pulse.
After the ACK pulse has finished: the host can start the bit retrieval if the last issued command was a read
command, or start a new command if the last command was a write command or a control command
(BACKGROUND, GO, GO_UNTIL or TRACE1). The ACK pulse is not issued earlier than 32 serial clock
cycles after the BDM command was issued. The end of the BDM command is assumed to be the 16th tick
of the last bit. This minimum delay assures enough time for the host to perceive the ACK pulse. Note also
that, there is no upper limit for the delay between the command and the related ACK pulse, since the
command execution depends upon the CPU bus, which in some cases could be very slow due to long
accesses taking place.This protocol allows a great flexibility for the POD designers, since it does not rely
on any accurate time measurement or short response time to any event in the serial communication.
BDM Clock
(Target MCU)
16 Cycles
Target
Transmits
ACK Pulse
High-Impedance
High-Impedance
32 Cycles
Speedup Pulse
Minimum Delay
From the BDM Command
BKGD Pin
Earliest
Start of
Next Bit
16th Tick of the
Last Command Bit
Figure 5-10. Target Acknowledge Pulse (ACK)
NOTE
If the ACK pulse was issued by the target, the host assumes the previous
command was executed. If the CPU enters wait or stop prior to executing a
hardware command, the ACK pulse will not be issued meaning that the
BDM command was not executed. After entering wait or stop mode, the
BDM command is no longer pending.
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Figure 5-11 shows the ACK handshake protocol in a command level timing diagram. The READ_BYTE
instruction is used as an example. First, the 8-bit instruction opcode is sent by the host, followed by the
address of the memory location to be read. The target BDM decodes the instruction. A bus cycle is grabbed
(free or stolen) by the BDM and it executes the READ_BYTE operation. Having retrieved the data, the
BDM issues an ACK pulse to the host controller, indicating that the addressed byte is ready to be retrieved.
After detecting the ACK pulse, the host initiates the byte retrieval process. Note that data is sent in the form
of a word and the host needs to determine which is the appropriate byte based on whether the address was
odd or even.
Target
BKGD Pin READ_BYTE
Host
Byte Address
Host
(2) Bytes are
Retrieved
New BDM
Command
Host
Target
Target
BDM Issues the
ACK Pulse (out of scale)
BDM Decodes
the Command
BDM Executes the
READ_BYTE Command
Figure 5-11. Handshake Protocol at Command Level
Differently from the normal bit transfer (where the host initiates the transmission), the serial interface ACK
handshake pulse is initiated by the target MCU by issuing a negative edge in the BKGD pin. The hardware
handshake protocol in Figure 5-10 specifies the timing when the BKGD pin is being driven, so the host
should follow this timing constraint in order to avoid the risk of an electrical conflict in the BKGD pin.
NOTE
The only place the BKGD pin can have an electrical conflict is when one
side is driving low and the other side is issuing a speedup pulse (high). Other
“highs” are pulled rather than driven. However, at low rates the time of the
speedup pulse can become lengthy and so the potential conflict time
becomes longer as well.
The ACK handshake protocol does not support nested ACK pulses. If a BDM command is not
acknowledge by an ACK pulse, the host needs to abort the pending command first in order to be able to
issue a new BDM command. When the CPU enters wait or stop while the host issues a hardware command
(e.g., WRITE_BYTE), the target discards the incoming command due to the wait or stop being detected.
Therefore, the command is not acknowledged by the target, which means that the ACK pulse will not be
issued in this case. After a certain time the host (not aware of stop or wait) should decide to abort any
possible pending ACK pulse in order to be sure a new command can be issued. Therefore, the protocol
provides a mechanism in which a command, and its corresponding ACK, can be aborted.
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NOTE
The ACK pulse does not provide a time out. This means for the GO_UNTIL
command that it can not be distinguished if a stop or wait has been executed
(command discarded and ACK not issued) or if the “UNTIL” condition
(BDM active) is just not reached yet. Hence in any case where the ACK
pulse of a command is not issued the possible pending command should be
aborted before issuing a new command. See the handshake abort procedure
described in Section 5.4.8, “Hardware Handshake Abort Procedure”.
5.4.8
Hardware Handshake Abort Procedure
The abort procedure is based on the SYNC command. In order to abort a command, which had not issued
the corresponding ACK pulse, the host controller should generate a low pulse in the BKGD pin by driving
it low for at least 128 serial clock cycles and then driving it high for one serial clock cycle, providing a
speedup pulse. By detecting this long low pulse in the BKGD pin, the target executes the SYNC protocol,
see Section 5.4.9, “SYNC — Request Timed Reference Pulse”, and assumes that the pending command
and therefore the related ACK pulse, are being aborted. Therefore, after the SYNC protocol has been
completed the host is free to issue new BDM commands. For BDM firmware READ or WRITE commands
it can not be guaranteed that the pending command is aborted when issuing a SYNC before the
corresponding ACK pulse. There is a short latency time from the time the READ or WRITE access begins
until it is finished and the corresponding ACK pulse is issued. The latency time depends on the firmware
READ or WRITE command that is issued and on the selected bus clock rate. When the SYNC command
starts during this latency time the READ or WRITE command will not be aborted, but the corresponding
ACK pulse will be aborted. A pending GO, TRACE1 or GO_UNTIL command can not be aborted. Only
the corresponding ACK pulse can be aborted by the SYNC command.
Although it is not recommended, the host could abort a pending BDM command by issuing a low pulse in
the BKGD pin shorter than 128 serial clock cycles, which will not be interpreted as the SYNC command.
The ACK is actually aborted when a negative edge is perceived by the target in the BKGD pin. The short
abort pulse should have at least 4 clock cycles keeping the BKGD pin low, in order to allow the negative
edge to be detected by the target. In this case, the target will not execute the SYNC protocol but the pending
command will be aborted along with the ACK pulse. The potential problem with this abort procedure is
when there is a conflict between the ACK pulse and the short abort pulse. In this case, the target may not
perceive the abort pulse. The worst case is when the pending command is a read command (i.e.,
READ_BYTE). If the abort pulse is not perceived by the target the host will attempt to send a new
command after the abort pulse was issued, while the target expects the host to retrieve the accessed
memory byte. In this case, host and target will run out of synchronism. However, if the command to be
aborted is not a read command the short abort pulse could be used. After a command is aborted the target
assumes the next negative edge, after the abort pulse, is the first bit of a new BDM command.
NOTE
The details about the short abort pulse are being provided only as a reference
for the reader to better understand the BDM internal behavior. It is not
recommended that this procedure be used in a real application.
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Since the host knows the target serial clock frequency, the SYNC command (used to abort a command)
does not need to consider the lower possible target frequency. In this case, the host could issue a SYNC
very close to the 128 serial clock cycles length. Providing a small overhead on the pulse length in order to
assure the SYNC pulse will not be misinterpreted by the target. See Section 5.4.9, “SYNC — Request
Timed Reference Pulse”.
Figure 5-12 shows a SYNC command being issued after a READ_BYTE, which aborts the READ_BYTE
command. Note that, after the command is aborted a new command could be issued by the host computer.
READ_BYTE CMD is Aborted
by the SYNC Request
(Out of Scale)
BKGD Pin READ_BYTE
Host
Memory Address
SYNC Response
From the Target
(Out of Scale)
READ_STATUS
Target
Host
BDM Decode
and Starts to Execute
the READ_BYTE Command
Target
New BDM Command
Host
Target
New BDM Command
Figure 5-12. ACK Abort Procedure at the Command Level
NOTE
Figure 5-12 does not represent the signals in a true timing scale
Figure 5-13 shows a conflict between the ACK pulse and the SYNC request pulse. This conflict could
occur if a POD device is connected to the target BKGD pin and the target is already in debug active mode.
Consider that the target CPU is executing a pending BDM command at the exact moment the POD is being
connected to the BKGD pin. In this case, an ACK pulse is issued along with the SYNC command. In this
case, there is an electrical conflict between the ACK speedup pulse and the SYNC pulse. Since this is not
a probable situation, the protocol does not prevent this conflict from happening.
At Least 128 Cycles
BDM Clock
(Target MCU)
ACK Pulse
Target MCU
Drives to
BKGD Pin
Host
Drives SYNC
To BKGD Pin
High-Impedance
Host and
Target Drive
to BKGD Pin
Electrical Conflict
Speedup Pulse
Host SYNC Request Pulse
BKGD Pin
16 Cycles
Figure 5-13. ACK Pulse and SYNC Request Conflict
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NOTE
This information is being provided so that the MCU integrator will be aware
that such a conflict could occur.
The hardware handshake protocol is enabled by the ACK_ENABLE and disabled by the ACK_DISABLE
BDM commands. This provides backwards compatibility with the existing POD devices which are not
able to execute the hardware handshake protocol. It also allows for new POD devices, that support the
hardware handshake protocol, to freely communicate with the target device. If desired, without the need
for waiting for the ACK pulse.
The commands are described as follows:
• ACK_ENABLE — enables the hardware handshake protocol. The target will issue the ACK pulse
when a CPU command is executed by the CPU. The ACK_ENABLE command itself also has the
ACK pulse as a response.
• ACK_DISABLE — disables the ACK pulse protocol. In this case, the host needs to use the worst
case delay time at the appropriate places in the protocol.
The default state of the BDM after reset is hardware handshake protocol disabled.
All the read commands will ACK (if enabled) when the data bus cycle has completed and the data is then
ready for reading out by the BKGD serial pin. All the write commands will ACK (if enabled) after the data
has been received by the BDM through the BKGD serial pin and when the data bus cycle is complete. See
Section 5.4.3, “BDM Hardware Commands” and Section 5.4.4, “Standard BDM Firmware Commands”
for more information on the BDM commands.
The ACK_ENABLE sends an ACK pulse when the command has been completed. This feature could be
used by the host to evaluate if the target supports the hardware handshake protocol. If an ACK pulse is
issued in response to this command, the host knows that the target supports the hardware handshake
protocol. If the target does not support the hardware handshake protocol the ACK pulse is not issued. In
this case, the ACK_ENABLE command is ignored by the target since it is not recognized as a valid
command.
The BACKGROUND command will issue an ACK pulse when the CPU changes from normal to
background mode. The ACK pulse related to this command could be aborted using the SYNC command.
The GO command will issue an ACK pulse when the CPU exits from background mode. The ACK pulse
related to this command could be aborted using the SYNC command.
The GO_UNTIL command is equivalent to a GO command with exception that the ACK pulse, in this
case, is issued when the CPU enters into background mode. This command is an alternative to the GO
command and should be used when the host wants to trace if a breakpoint match occurs and causes the
CPU to enter active background mode. Note that the ACK is issued whenever the CPU enters BDM, which
could be caused by a breakpoint match or by a BGND instruction being executed. The ACK pulse related
to this command could be aborted using the SYNC command.
The TRACE1 command has the related ACK pulse issued when the CPU enters background active mode
after one instruction of the application program is executed. The ACK pulse related to this command could
be aborted using the SYNC command.
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5.4.9
SYNC — Request Timed Reference Pulse
The SYNC command is unlike other BDM commands because the host does not necessarily know the
correct communication speed to use for BDM communications until after it has analyzed the response to
the SYNC command. To issue a SYNC command, the host should perform the following steps:
1. Drive the BKGD pin low for at least 128 cycles at the lowest possible BDM serial communication
frequency (The lowest serial communication frequency is determined by the settings for the VCO
clock (CPMUSYNR). The BDM clock frequency is always VCO clock frequency divided by 8.)
2. Drive BKGD high for a brief speedup pulse to get a fast rise time (this speedup pulse is typically
one cycle of the host clock.)
3. Remove all drive to the BKGD pin so it reverts to high impedance.
4. Listen to the BKGD pin for the sync response pulse.
Upon detecting the SYNC request from the host, the target performs the following steps:
1. Discards any incomplete command received or bit retrieved.
2. Waits for BKGD to return to a logic one.
3. Delays 16 cycles to allow the host to stop driving the high speedup pulse.
4. Drives BKGD low for 128 cycles at the current BDM serial communication frequency.
5. Drives a one-cycle high speedup pulse to force a fast rise time on BKGD.
6. Removes all drive to the BKGD pin so it reverts to high impedance.
The host measures the low time of this 128 cycle SYNC response pulse and determines the correct speed
for subsequent BDM communications. Typically, the host can determine the correct communication speed
within a few percent of the actual target speed and the communication protocol can easily tolerate speed
errors of several percent.
As soon as the SYNC request is detected by the target, any partially received command or bit retrieved is
discarded. This is referred to as a soft-reset, equivalent to a time-out in the serial communication. After the
SYNC response, the target will consider the next negative edge (issued by the host) as the start of a new
BDM command or the start of new SYNC request.
Another use of the SYNC command pulse is to abort a pending ACK pulse. The behavior is exactly the
same as in a regular SYNC command. Note that one of the possible causes for a command to not be
acknowledged by the target is a host-target synchronization problem. In this case, the command may not
have been understood by the target and so an ACK response pulse will not be issued.
5.4.10
Instruction Tracing
When a TRACE1 command is issued to the BDM in active BDM, the CPU exits the standard BDM
firmware and executes a single instruction in the user code. Once this has occurred, the CPU is forced to
return to the standard BDM firmware and the BDM is active and ready to receive a new command. If the
TRACE1 command is issued again, the next user instruction will be executed. This facilitates stepping or
tracing through the user code one instruction at a time.
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If an interrupt is pending when a TRACE1 command is issued, the interrupt stacking operation occurs but
no user instruction is executed. Once back in standard BDM firmware execution, the program counter
points to the first instruction in the interrupt service routine.
Be aware when tracing through the user code that the execution of the user code is done step by step but
all peripherals are free running. Hence possible timing relations between CPU code execution and
occurrence of events of other peripherals no longer exist.
Do not trace the CPU instruction BGND used for soft breakpoints. Tracing over the BGND instruction will
result in a return address pointing to BDM firmware address space.
When tracing through user code which contains stop or wait instructions the following will happen when
the stop or wait instruction is traced:
The CPU enters stop or wait mode and the TRACE1 command can not be finished before leaving
the low power mode. This is the case because BDM active mode can not be entered after CPU
executed the stop instruction. However all BDM hardware commands except the BACKGROUND
command are operational after tracing a stop or wait instruction and still being in stop or wait
mode. If system stop mode is entered (all bus masters are in stop mode) no BDM command is
operational.
As soon as stop or wait mode is exited the CPU enters BDM active mode and the saved PC value
points to the entry of the corresponding interrupt service routine.
In case the handshake feature is enabled the corresponding ACK pulse of the TRACE1 command
will be discarded when tracing a stop or wait instruction. Hence there is no ACK pulse when BDM
active mode is entered as part of the TRACE1 command after CPU exited from stop or wait mode.
All valid commands sent during CPU being in stop or wait mode or after CPU exited from stop or
wait mode will have an ACK pulse. The handshake feature becomes disabled only when system
stop mode has been reached. Hence after a system stop mode the handshake feature must be
enabled again by sending the ACK_ENABLE command.
5.4.11
Serial Communication Time Out
The host initiates a host-to-target serial transmission by generating a falling edge on the BKGD pin. If
BKGD is kept low for more than 128 target clock cycles, the target understands that a SYNC command
was issued. In this case, the target will keep waiting for a rising edge on BKGD in order to answer the
SYNC request pulse. If the rising edge is not detected, the target will keep waiting forever without any
time-out limit.
Consider now the case where the host returns BKGD to logic one before 128 cycles. This is interpreted as
a valid bit transmission, and not as a SYNC request. The target will keep waiting for another falling edge
marking the start of a new bit. If, however, a new falling edge is not detected by the target within 512 clock
cycles since the last falling edge, a time-out occurs and the current command is discarded without affecting
memory or the operating mode of the MCU. This is referred to as a soft-reset.
If a read command is issued but the data is not retrieved within 512 serial clock cycles, a soft-reset will
occur causing the command to be disregarded. The data is not available for retrieval after the time-out has
occurred. This is the expected behavior if the handshake protocol is not enabled. In order to allow the data
to be retrieved even with a large clock frequency mismatch (between BDM and CPU) when the hardware
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handshake protocol is enabled, the time out between a read command and the data retrieval is disabled.
Therefore, the host could wait for more then 512 serial clock cycles and still be able to retrieve the data
from an issued read command. However, once the handshake pulse (ACK pulse) is issued, the time-out
feature is re-activated, meaning that the target will time out after 512 clock cycles. Therefore, the host
needs to retrieve the data within a 512 serial clock cycles time frame after the ACK pulse had been issued.
After that period, the read command is discarded and the data is no longer available for retrieval. Any
negative edge in the BKGD pin after the time-out period is considered to be a new command or a SYNC
request.
Note that whenever a partially issued command, or partially retrieved data, has occurred the time out in the
serial communication is active. This means that if a time frame higher than 512 serial clock cycles is
observed between two consecutive negative edges and the command being issued or data being retrieved
is not complete, a soft-reset will occur causing the partially received command or data retrieved to be
disregarded. The next negative edge in the BKGD pin, after a soft-reset has occurred, is considered by the
target as the start of a new BDM command, or the start of a SYNC request pulse.
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Chapter 6
S12S Debug Module (S12SDBGV2)
Table 6-1. Revision History
Revision Number
Revision
Date
Sections
Affected
02.07
13.DEC.2007
6.5
02.08
09.MAY.2008
General
Spelling corrections. Revision history format changed.
02.09
29.MAY.2008
6.4.5.4
Added note for end aligned, PurePC, rollover case.
6.1
Summary of Changes
Added application information
Introduction
The S12SDBG module provides an on-chip trace buffer with flexible triggering capability to allow nonintrusive debug of application software. The S12SDBG module is optimized for S12SCPU debugging.
Typically the S12SDBG module is used in conjunction with the S12SBDM module, whereby the user
configures the S12SDBG module for a debugging session over the BDM interface. Once configured the
S12SDBG module is armed and the device leaves BDM returning control to the user program, which is
then monitored by the S12SDBG module. Alternatively the S12SDBG module can be configured over a
serial interface using SWI routines.
6.1.1
Glossary Of Terms
COF: Change Of Flow. Change in the program flow due to a conditional branch, indexed jump or interrupt.
BDM: Background Debug Mode
S12SBDM: Background Debug Module
DUG: Device User Guide, describing the features of the device into which the DBG is integrated.
WORD: 16 bit data entity
Data Line: 20 bit data entity
CPU: S12SCPU module
DBG: S12SDBG module
POR: Power On Reset
Tag: Tags can be attached to CPU opcodes as they enter the instruction pipe. If the tagged opcode reaches
the execution stage a tag hit occurs.
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6.1.2
Overview
The comparators monitor the bus activity of the CPU module. A match can initiate a state sequencer
transition. On a transition to the Final State, bus tracing is triggered and/or a breakpoint can be generated.
Independent of comparator matches a transition to Final State with associated tracing and breakpoint can
be triggered immediately by writing to the TRIG control bit.
The trace buffer is visible through a 2-byte window in the register address map and can be read out using
standard 16-bit word reads. Tracing is disabled when the MCU system is secured.
6.1.3
•
•
•
•
•
•
•
Features
Three comparators (A, B and C)
— Comparators A compares the full address bus and full 16-bit data bus
— Comparator A features a data bus mask register
— Comparators B and C compare the full address bus only
— Each comparator features selection of read or write access cycles
— Comparator B allows selection of byte or word access cycles
— Comparator matches can initiate state sequencer transitions
Three comparator modes
— Simple address/data comparator match mode
— Inside address range mode, Addmin ≤ Address ≤ Addmax
— Outside address range match mode, Address < Addmin or Address > Addmax
Two types of matches
— Tagged — This matches just before a specific instruction begins execution
— Force — This is valid on the first instruction boundary after a match occurs
Two types of breakpoints
— CPU breakpoint entering BDM on breakpoint (BDM)
— CPU breakpoint executing SWI on breakpoint (SWI)
Trigger mode independent of comparators
— TRIG Immediate software trigger
Four trace modes
— Normal: change of flow (COF) PC information is stored (see 6.4.5.2.1) for change of flow
definition.
— Loop1: same as Normal but inhibits consecutive duplicate source address entries
— Detail: address and data for all cycles except free cycles and opcode fetches are stored
— Compressed Pure PC: all program counter addresses are stored
4-stage state sequencer for trace buffer control
— Tracing session trigger linked to Final State of state sequencer
— Begin and End alignment of tracing to trigger
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6.1.4
Modes of Operation
The DBG module can be used in all MCU functional modes.
During BDM hardware accesses and whilst the BDM module is active, CPU monitoring is disabled. When
the CPU enters active BDM Mode through a BACKGROUND command, the DBG module, if already
armed, remains armed.
The DBG module tracing is disabled if the MCU is secure, however, breakpoints can still be generated
Table 6-2. Mode Dependent Restriction Summary
BDM
Enable
BDM
Active
MCU
Secure
Comparator
Matches Enabled
Breakpoints
Possible
Tagging
Possible
Tracing
Possible
x
x
1
Yes
Yes
Yes
No
0
0
0
Yes
Only SWI
Yes
Yes
0
1
0
1
0
0
Yes
Yes
Yes
Yes
1
1
0
No
No
No
No
6.1.5
Active BDM not possible when not enabled
Block Diagram
TAGS
TAGHITS
BREAKPOINT REQUESTS
TO CPU
COMPARATOR A
COMPARATOR B
COMPARATOR C
COMPARATOR
MATCH CONTROL
CPU BUS
BUS INTERFACE
SECURE
MATCH0
MATCH1
TAG &
MATCH
CONTROL
LOGIC
TRANSITION
STATE
STATE SEQUENCER
STATE
MATCH2
TRACE
CONTROL
TRIGGER
TRACE BUFFER
READ TRACE DATA (DBG READ DATA BUS)
Figure 6-1. Debug Module Block Diagram
6.2
External Signal Description
There are no external signals associated with this module.
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6.3
6.3.1
Memory Map and Registers
Module Memory Map
A summary of the registers associated with the DBG sub-block is shown in Figure 6-2. Detailed
descriptions of the registers and bits are given in the subsections that follow.
Address
2
3
4
Name
Bit 7
6
0
TRIG
5
0
4
3
BDM
DBGBRK
0
0
0
0
0
0
2
0
1
Bit 0
SSF2
SSF1
0x0020
DBGC1
R
W
0x0021
DBGSR
R
W
0x0022
DBGTCR
R
W
0
0x0023
DBGC2
R
W
0
0
0
0
0
0
0x0024
DBGTBH
R
W
Bit 15
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
0x0025
DBGTBL
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0x0026
DBGCNT
R 1 TBF
W
0
0x0027
DBGSCRX
0
0
0
0
SC3
SC2
SC1
SC0
0x0027
DBGMFR
R
W
R
W
0
0
0
0
0
MC2
MC1
MC0
SZE
SZ
TAG
BRK
RW
RWE
NDB
COMPE
SZE
SZ
TAG
BRK
RW
RWE
0
0
TAG
BRK
RW
RWE
0
0
0
0
0
0
0x0028
0x0028
0x0028
R
W
R
DBGBCTL
W
R
DBGCCTL
W
DBGACTL
ARM
1
TBF
TSOURCE
COMRV
SSF0
0
TRCMOD
TALIGN
ABCM
CNT
0x0029
DBGXAH
R
W
0x002A
DBGXAM
R
W
Bit 15
14
13
12
11
0x002B
DBGXAL
R
W
Bit 7
6
5
4
0x002C
DBGADH
R
W
Bit 15
14
13
0x002D
DBGADL
R
W
Bit 7
6
5
0
0
COMPE
COMPE
Bit 17
Bit 16
10
9
Bit 8
3
2
1
Bit 0
12
11
10
9
Bit 8
4
3
2
1
Bit 0
Figure 6-2. Quick Reference to DBG Registers
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Address
Name
0x002E
DBGADHM
2
3
4
6
5
4
3
2
1
Bit 0
Bit 15
14
13
12
11
10
9
Bit 8
1
Bit 0
R
Bit 7
6
5
4
3
2
W
This bit is visible at DBGCNT[7] and DBGSR[7]
This represents the contents if the Comparator A control register is blended into this address.
This represents the contents if the Comparator B control register is blended into this address
This represents the contents if the Comparator C control register is blended into this address
0x002F
1
R
W
Bit 7
DBGADLM
Figure 6-2. Quick Reference to DBG Registers
6.3.2
Register Descriptions
This section consists of the DBG control and trace buffer register descriptions in address order. Each
comparator has a bank of registers that are visible through an 8-byte window between 0x0028 and 0x002F
in the DBG module register address map. When ARM is set in DBGC1, the only bits in the DBG module
registers that can be written are ARM, TRIG, and COMRV[1:0]
6.3.2.1
Debug Control Register 1 (DBGC1)
Address: 0x0020
7
R
W
Reset
ARM
6
5
0
0
TRIG
0
0
0
4
3
BDM
DBGBRK
0
0
2
1
0
0
0
COMRV
0
0
= Unimplemented or Reserved
Figure 6-3. Debug Control Register (DBGC1)
Read: Anytime
Write: Bits 7, 1, 0 anytime
Bit 6 can be written anytime but always reads back as 0.
Bits 4:3 anytime DBG is not armed.
NOTE
When disarming the DBG by clearing ARM with software, the contents of
bits[4:3] are not affected by the write, since up until the write operation,
ARM = 1 preventing these bits from being written. These bits must be
cleared using a second write if required.
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Table 6-3. DBGC1 Field Descriptions
Field
Description
7
ARM
Arm Bit — The ARM bit controls whether the DBG module is armed. This bit can be set and cleared by user
software and is automatically cleared on completion of a debug session, or if a breakpoint is generated with
tracing not enabled. On setting this bit the state sequencer enters State1.
0 Debugger disarmed
1 Debugger armed
6
TRIG
Immediate Trigger Request Bit — This bit when written to 1 requests an immediate trigger independent of state
sequencer status. When tracing is complete a forced breakpoint may be generated depending upon DBGBRK
and BDM bit settings. This bit always reads back a 0. Writing a 0 to this bit has no effect. If the
DBGTCR_TSOURCE bit is clear no tracing is carried out. If tracing has already commenced using BEGIN trigger
alignment, it continues until the end of the tracing session as defined by the TALIGN bit, thus TRIG has no affect.
In secure mode tracing is disabled and writing to this bit cannot initiate a tracing session.
The session is ended by setting TRIG and ARM simultaneously.
0 Do not trigger until the state sequencer enters the Final State.
1 Trigger immediately
4
BDM
Background Debug Mode Enable — This bit determines if a breakpoint causes the system to enter Background
Debug Mode (BDM) or initiate a Software Interrupt (SWI). If this bit is set but the BDM is not enabled by the
ENBDM bit in the BDM module, then breakpoints default to SWI.
0 Breakpoint to Software Interrupt if BDM inactive. Otherwise no breakpoint.
1 Breakpoint to BDM, if BDM enabled. Otherwise breakpoint to SWI
3
DBGBRK
S12SDBG Breakpoint Enable Bit — The DBGBRK bit controls whether the debugger will request a breakpoint
on reaching the state sequencer Final State. If tracing is enabled, the breakpoint is generated on completion
of the tracing session. If tracing is not enabled, the breakpoint is generated immediately.
0 No Breakpoint generated
1 Breakpoint generated
1–0
COMRV
Comparator Register Visibility Bits — These bits determine which bank of comparator register is visible in the
8-byte window of the S12SDBG module address map, located between 0x0028 to 0x002F. Furthermore these
bits determine which register is visible at the address 0x0027. See Table 6-4.
Table 6-4. COMRV Encoding
6.3.2.2
COMRV
Visible Comparator
Visible Register at 0x0027
00
Comparator A
DBGSCR1
01
Comparator B
DBGSCR2
10
Comparator C
DBGSCR3
11
None
DBGMFR
Debug Status Register (DBGSR)
Address: 0x0021
R
7
6
5
4
3
2
1
0
TBF
0
0
0
0
SSF2
SSF1
SSF0
—
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
POR
= Unimplemented or Reserved
Figure 6-4. Debug Status Register (DBGSR)
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Read: Anytime
Write: Never
Table 6-5. DBGSR Field Descriptions
Field
Description
7
TBF
Trace Buffer Full — The TBF bit indicates that the trace buffer has stored 64 or more lines of data since it was
last armed. If this bit is set, then all 64 lines will be valid data, regardless of the value of DBGCNT bits. The TBF
bit is cleared when ARM in DBGC1 is written to a one. The TBF is cleared by the power on reset initialization.
Other system generated resets have no affect on this bit
This bit is also visible at DBGCNT[7]
2–0
SSF[2:0]
State Sequencer Flag Bits — The SSF bits indicate in which state the State Sequencer is currently in. During
a debug session on each transition to a new state these bits are updated. If the debug session is ended by
software clearing the ARM bit, then these bits retain their value to reflect the last state of the state sequencer
before disarming. If a debug session is ended by an internal event, then the state sequencer returns to state0
and these bits are cleared to indicate that state0 was entered during the session. On arming the module the state
sequencer enters state1 and these bits are forced to SSF[2:0] = 001. See Table 6-6.
Table 6-6. SSF[2:0] — State Sequence Flag Bit Encoding
6.3.2.3
SSF[2:0]
Current State
000
State0 (disarmed)
001
State1
010
State2
011
State3
100
Final State
101,110,111
Reserved
Debug Trace Control Register (DBGTCR)
Address: 0x0022
7
R
0
W
Reset
0
6
TSOURCE
0
5
4
0
0
0
0
3
2
TRCMOD
0
1
0
0
0
0
TALIGN
0
Figure 6-5. Debug Trace Control Register (DBGTCR)
Read: Anytime
Write: Bit 6 only when DBG is neither secure nor armed.Bits 3,2,0 anytime the module is disarmed.
Table 6-7. DBGTCR Field Descriptions
Field
Description
6
TSOURCE
Trace Source Control Bit — The TSOURCE bit enables a tracing session given a trigger condition. If the MCU
system is secured, this bit cannot be set and tracing is inhibited.
This bit must be set to read the trace buffer.
0 Debug session without tracing requested
1 Debug session with tracing requested
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Table 6-7. DBGTCR Field Descriptions (continued)
Field
Description
3–2
TRCMOD
Trace Mode Bits — See 6.4.5.2 for detailed Trace Mode descriptions. In Normal Mode, change of flow
information is stored. In Loop1 Mode, change of flow information is stored but redundant entries into trace
memory are inhibited. In Detail Mode, address and data for all memory and register accesses is stored. In
Compressed Pure PC mode the program counter value for each instruction executed is stored. See Table 6-8.
0
TALIGN
Trigger Align Bit — This bit controls whether the trigger is aligned to the beginning or end of a tracing session.
0 Trigger at end of stored data
1 Trigger before storing data
Table 6-8. TRCMOD Trace Mode Bit Encoding
6.3.2.4
TRCMOD
Description
00
Normal
01
Loop1
10
Detail
11
Compressed Pure PC
Debug Control Register2 (DBGC2)
Address: 0x0023
R
7
6
5
4
3
2
0
0
0
0
0
0
0
0
0
0
0
1
ABCM
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 6-6. Debug Control Register2 (DBGC2)
Read: Anytime
Write: Anytime the module is disarmed.
This register configures the comparators for range matching.
Table 6-9. DBGC2 Field Descriptions
Field
Description
1–0
ABCM[1:0]
A and B Comparator Match Control — These bits determine the A and B comparator match mapping as
described in Table 6-10.
Table 6-10. ABCM Encoding
ABCM
Description
00
Match0 mapped to comparator A match: Match1 mapped to comparator B match.
01
Match 0 mapped to comparator A/B inside range: Match1 disabled.
10
Match 0 mapped to comparator A/B outside range: Match1 disabled.
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Table 6-10. ABCM Encoding
ABCM
Description
11
Reserved(1)
1. Currently defaults to Comparator A, Comparator B disabled
6.3.2.5
Debug Trace Buffer Register (DBGTBH:DBGTBL)
Address: 0x0024, 0x0025
15
R
W
14
13
12
11
10
9
Bit 15 Bit 14 Bit 13 Bit 12 Bit 11 Bit 10 Bit 9
8
7
6
5
4
3
2
1
0
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
POR
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Other
Resets
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
Figure 6-7. Debug Trace Buffer Register (DBGTB)
Read: Only when unlocked AND unsecured AND not armed AND TSOURCE set.
Write: Aligned word writes when disarmed unlock the trace buffer for reading but do not affect trace buffer
contents.
Table 6-11. DBGTB Field Descriptions
Field
Description
15–0
Bit[15:0]
Trace Buffer Data Bits — The Trace Buffer Register is a window through which the 20-bit wide data lines of the
Trace Buffer may be read 16 bits at a time. Each valid read of DBGTB increments an internal trace buffer pointer
which points to the next address to be read. When the ARM bit is set the trace buffer is locked to prevent reading.
The trace buffer can only be unlocked for reading by writing to DBGTB with an aligned word write when the
module is disarmed. The DBGTB register can be read only as an aligned word, any byte reads or misaligned
access of these registers return 0 and do not cause the trace buffer pointer to increment to the next trace buffer
address. Similarly reads while the debugger is armed or with the TSOURCE bit clear, return 0 and do not affect
the trace buffer pointer. The POR state is undefined. Other resets do not affect the trace buffer contents.
6.3.2.6
Debug Count Register (DBGCNT)
Address: 0x0026
R
7
6
TBF
0
—
0
—
0
5
4
3
2
1
0
—
0
—
0
—
0
CNT
W
Reset
POR
—
0
—
0
—
0
= Unimplemented or Reserved
Figure 6-8. Debug Count Register (DBGCNT)
Read: Anytime
Write: Never
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S12S Debug Module (S12SDBGV2)
Table 6-12. DBGCNT Field Descriptions
Field
Description
7
TBF
Trace Buffer Full — The TBF bit indicates that the trace buffer has stored 64 or more lines of data since it was
last armed. If this bit is set, then all 64 lines will be valid data, regardless of the value of DBGCNT bits. The TBF
bit is cleared when ARM in DBGC1 is written to a one. The TBF is cleared by the power on reset initialization.
Other system generated resets have no affect on this bit
This bit is also visible at DBGSR[7]
5–0
CNT[5:0]
Count Value — The CNT bits indicate the number of valid data 20-bit data lines stored in the Trace Buffer.
Table 6-13 shows the correlation between the CNT bits and the number of valid data lines in the Trace Buffer.
When the CNT rolls over to zero, the TBF bit in DBGSR is set and incrementing of CNT will continue in endtrigger mode. The DBGCNT register is cleared when ARM in DBGC1 is written to a one. The DBGCNT register
is cleared by power-on-reset initialization but is not cleared by other system resets. Thus should a reset occur
during a debug session, the DBGCNT register still indicates after the reset, the number of valid trace buffer
entries stored before the reset occurred. The DBGCNT register is not decremented when reading from the trace
buffer.
Table 6-13. CNT Decoding Table
6.3.2.7
TBF
CNT[5:0]
Description
0
000000
No data valid
0
000001
000010
000100
000110
..
111111
1 line valid
2 lines valid
4 lines valid
6 lines valid
..
63 lines valid
1
000000
64 lines valid; if using Begin trigger alignment,
ARM bit will be cleared and the tracing session ends.
1
000001
..
..
111110
64 lines valid,
oldest data has been overwritten by most recent data
Debug State Control Registers
There is a dedicated control register for each of the state sequencer states 1 to 3 that determines if
transitions from that state are allowed, depending upon comparator matches or tag hits, and defines the
next state for the state sequencer following a match. The three debug state control registers are located at
the same address in the register address map (0x0027). Each register can be accessed using the COMRV
bits in DBGC1 to blend in the required register. The COMRV = 11 value blends in the match flag register
(DBGMFR).
Table 6-14. State Control Register Access Encoding
COMRV
Visible State Control Register
00
DBGSCR1
01
DBGSCR2
10
DBGSCR3
11
DBGMFR
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S12S Debug Module (S12SDBGV2)
6.3.2.7.1
Debug State Control Register 1 (DBGSCR1)
Address: 0x0027
R
7
6
5
4
0
0
0
0
0
0
0
W
Reset
0
3
2
1
0
SC3
SC2
SC1
SC0
0
0
0
0
= Unimplemented or Reserved
Figure 6-9. Debug State Control Register 1 (DBGSCR1)
Read: If COMRV[1:0] = 00
Write: If COMRV[1:0] = 00 and DBG is not armed.
This register is visible at 0x0027 only with COMRV[1:0] = 00. The state control register 1 selects the
targeted next state whilst in State1. The matches refer to the match channels of the comparator match
control logic as depicted in Figure 6-1 and described in 6.3.2.8.1. Comparators must be enabled by setting
the comparator enable bit in the associated DBGXCTL control register.
Table 6-15. DBGSCR1 Field Descriptions
Field
3–0
SC[3:0]
Description
These bits select the targeted next state whilst in State1, based upon the match event.
Table 6-16. State1 Sequencer Next State Selection
SC[3:0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Description (Unspecified matches have no effect)
Any match to Final State
Match1 to State3
Match2 to State2
Match1 to State2
Match0 to State2....... Match1 to State3
Match1 to State3.........Match0 to Final State
Match0 to State2....... Match2 to State3
Either Match0 or Match1 to State2
Reserved
Match0 to State3
Reserved
Reserved
Reserved
Either Match0 or Match2 to Final State........Match1 to State2
Reserved
Reserved
The priorities described in Table 6-36 dictate that in the case of simultaneous matches, a match leading to
final state has priority followed by the match on the lower channel number (0,1,2). Thus with
SC[3:0]=1101 a simultaneous match0/match1 transitions to final state.
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S12S Debug Module (S12SDBGV2)
6.3.2.7.2
Debug State Control Register 2 (DBGSCR2)
Address: 0x0027
R
7
6
5
4
0
0
0
0
0
0
0
W
Reset
0
3
2
1
0
SC3
SC2
SC1
SC0
0
0
0
0
= Unimplemented or Reserved
Figure 6-10. Debug State Control Register 2 (DBGSCR2)
Read: If COMRV[1:0] = 01
Write: If COMRV[1:0] = 01 and DBG is not armed.
This register is visible at 0x0027 only with COMRV[1:0] = 01. The state control register 2 selects the
targeted next state whilst in State2. The matches refer to the match channels of the comparator match
control logic as depicted in Figure 6-1 and described in 6.3.2.8.1. Comparators must be enabled by setting
the comparator enable bit in the associated DBGXCTL control register.
Table 6-17. DBGSCR2 Field Descriptions
Field
3–0
SC[3:0]
Description
These bits select the targeted next state whilst in State2, based upon the match event.
Table 6-18. State2 —Sequencer Next State Selection
SC[3:0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Description (Unspecified matches have no effect)
Match0 to State1....... Match2 to State3.
Match1 to State3
Match2 to State3
Match1 to State3....... Match0 Final State
Match1 to State1....... Match2 to State3.
Match2 to Final State
Match2 to State1..... Match0 to Final State
Either Match0 or Match1 to Final State
Reserved
Reserved
Reserved
Reserved
Either Match0 or Match1 to Final State........Match2 to State3
Reserved
Reserved
Either Match0 or Match1 to Final State........Match2 to State1
The priorities described in Table 6-36 dictate that in the case of simultaneous matches, a match leading to
final state has priority followed by the match on the lower channel number (0,1,2)
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S12S Debug Module (S12SDBGV2)
6.3.2.7.3
Debug State Control Register 3 (DBGSCR3)
Address: 0x0027
R
7
6
5
4
0
0
0
0
0
0
0
W
Reset
0
3
2
1
0
SC3
SC2
SC1
SC0
0
0
0
0
= Unimplemented or Reserved
Figure 6-11. Debug State Control Register 3 (DBGSCR3)
Read: If COMRV[1:0] = 10
Write: If COMRV[1:0] = 10 and DBG is not armed.
This register is visible at 0x0027 only with COMRV[1:0] = 10. The state control register three selects the
targeted next state whilst in State3. The matches refer to the match channels of the comparator match
control logic as depicted in Figure 6-1 and described in 6.3.2.8.1. Comparators must be enabled by setting
the comparator enable bit in the associated DBGXCTL control register.
Table 6-19. DBGSCR3 Field Descriptions
Field
3–0
SC[3:0]
Description
These bits select the targeted next state whilst in State3, based upon the match event.
Table 6-20. State3 — Sequencer Next State Selection
SC[3:0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
Description (Unspecified matches have no effect)
Match0 to State1
Match2 to State2........ Match1 to Final State
Match0 to Final State....... Match1 to State1
Match1 to Final State....... Match2 to State1
Match1 to State2
Match1 to Final State
Match2 to State2........ Match0 to Final State
Match0 to Final State
Reserved
Reserved
Either Match1 or Match2 to State1....... Match0 to Final State
Reserved
Reserved
Either Match1 or Match2 to Final State....... Match0 to State1
Match0 to State2....... Match2 to Final State
Reserved
The priorities described in Table 6-36 dictate that in the case of simultaneous matches, a match leading to
final state has priority followed by the match on the lower channel number (0,1,2).
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167
S12S Debug Module (S12SDBGV2)
6.3.2.7.4
Debug Match Flag Register (DBGMFR)
Address: 0x0027
R
7
6
5
4
3
2
1
0
0
0
0
0
0
MC2
MC1
MC0
0
0
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 6-12. Debug Match Flag Register (DBGMFR)
Read: If COMRV[1:0] = 11
Write: Never
DBGMFR is visible at 0x0027 only with COMRV[1:0] = 11. It features 3 flag bits each mapped directly
to a channel. Should a match occur on the channel during the debug session, then the corresponding flag
is set and remains set until the next time the module is armed by writing to the ARM bit. Thus the contents
are retained after a debug session for evaluation purposes. These flags cannot be cleared by software, they
are cleared only when arming the module. A set flag does not inhibit the setting of other flags. Once a flag
is set, further comparator matches on the same channel in the same session have no affect on that flag.
6.3.2.8
Comparator Register Descriptions
Each comparator has a bank of registers that are visible through an 8-byte window in the DBG module
register address map. Comparator A consists of 8 register bytes (3 address bus compare registers, two data
bus compare registers, two data bus mask registers and a control register). Comparator B consists of four
register bytes (three address bus compare registers and a control register). Comparator C consists of four
register bytes (three address bus compare registers and a control register).
Each set of comparator registers can be accessed using the COMRV bits in the DBGC1 register.
Unimplemented registers (e.g. Comparator B data bus and data bus masking) read as zero and cannot be
written. The control register for comparator B differs from those of comparators A and C.
Table 6-21. Comparator Register Layout
0x0028
CONTROL
Read/Write
Comparators A,B and C
0x0029
ADDRESS HIGH
Read/Write
Comparators A,B and C
0x002A
ADDRESS MEDIUM
Read/Write
Comparators A,B and C
0x002B
ADDRESS LOW
Read/Write
Comparators A,B and C
0x002C
DATA HIGH COMPARATOR
Read/Write
Comparator A only
0x002D
DATA LOW COMPARATOR
Read/Write
Comparator A only
0x002E
DATA HIGH MASK
Read/Write
Comparator A only
0x002F
DATA LOW MASK
Read/Write
Comparator A only
6.3.2.8.1
Debug Comparator Control Register (DBGXCTL)
The contents of this register bits 7 and 6 differ depending upon which comparator registers are visible in
the 8-byte window of the DBG module register address map.
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S12S Debug Module (S12SDBGV2)
Address: 0x0028
R
W
7
6
5
4
3
2
1
0
SZE
SZ
TAG
BRK
RW
RWE
NDB
COMPE
0
0
0
0
0
0
0
Reset
0
= Unimplemented or Reserved
Figure 6-13. Debug Comparator Control Register DBGACTL (Comparator A)
Address: 0x0028
R
W
7
6
5
4
3
2
SZE
SZ
TAG
BRK
RW
RWE
0
0
0
0
0
Reset
0
1
0
0
0
COMPE
0
= Unimplemented or Reserved
Figure 6-14. Debug Comparator Control Register DBGBCTL (Comparator B)
Address: 0x0028
R
7
6
0
0
W
Reset
0
0
5
4
3
2
TAG
BRK
RW
RWE
0
0
0
0
1
0
0
0
COMPE
0
= Unimplemented or Reserved
Figure 6-15. Debug Comparator Control Register DBGCCTL (Comparator C)
Read: DBGACTL if COMRV[1:0] = 00
DBGBCTL if COMRV[1:0] = 01
DBGCCTL if COMRV[1:0] = 10
Write: DBGACTL if COMRV[1:0] = 00 and DBG not armed
DBGBCTL if COMRV[1:0] = 01 and DBG not armed
DBGCCTL if COMRV[1:0] = 10 and DBG not armed
Table 6-22. DBGXCTL Field Descriptions
Field
Description
7
SZE
(Comparators
A and B)
Size Comparator Enable Bit — The SZE bit controls whether access size comparison is enabled for the
associated comparator. This bit is ignored if the TAG bit in the same register is set.
0 Word/Byte access size is not used in comparison
1 Word/Byte access size is used in comparison
6
SZ
(Comparators
A and B)
Size Comparator Value Bit — The SZ bit selects either word or byte access size in comparison for the
associated comparator. This bit is ignored if the SZE bit is cleared or if the TAG bit in the same register is set.
0 Word access size is compared
1 Byte access size is compared
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S12S Debug Module (S12SDBGV2)
Table 6-22. DBGXCTL Field Descriptions (continued)
Field
Description
5
TAG
Tag Select— This bit controls whether the comparator match has immediate effect, causing an immediate
state sequencer transition or tag the opcode at the matched address. Tagged opcodes trigger only if they
reach the execution stage of the instruction queue.
0 Allow state sequencer transition immediately on match
1 On match, tag the opcode. If the opcode is about to be executed allow a state sequencer transition
4
BRK
Break— This bit controls whether a comparator match terminates a debug session immediately, independent
of state sequencer state. To generate an immediate breakpoint the module breakpoints must be enabled
using the DBGC1 bit DBGBRK.
0 The debug session termination is dependent upon the state sequencer and trigger conditions.
1 A match on this channel terminates the debug session immediately; breakpoints if active are generated,
tracing, if active, is terminated and the module disarmed.
3
RW
Read/Write Comparator Value Bit — The RW bit controls whether read or write is used in compare for the
associated comparator. The RW bit is not used if RWE = 0. This bit is ignored if the TAG bit in the same
register is set.
0 Write cycle is matched1Read cycle is matched
2
RWE
Read/Write Enable Bit — The RWE bit controls whether read or write comparison is enabled for the
associated comparator.This bit is ignored if the TAG bit in the same register is set
0 Read/Write is not used in comparison
1 Read/Write is used in comparison
Not Data Bus — The NDB bit controls whether the match occurs when the data bus matches the comparator
1
register value or when the data bus differs from the register value. This bit is ignored if the TAG bit in the same
NDB
(Comparator A) register is set. This bit is only available for comparator A.
0 Match on data bus equivalence to comparator register contents
1 Match on data bus difference to comparator register contents
0
COMPE
Determines if comparator is enabled
0 The comparator is not enabled
1 The comparator is enabled
Table 6-23 shows the effect for RWE and RW on the comparison conditions. These bits are ignored if the
corresponding TAG bit is set since the match occurs based on the tagged opcode reaching the execution
stage of the instruction queue.
Table 6-23. Read or Write Comparison Logic Table
RWE Bit
RW Bit
RW Signal
Comment
0
x
0
RW not used in comparison
0
x
1
RW not used in comparison
1
0
0
Write data bus
1
0
1
No match
1
1
0
No match
1
1
1
Read data bus
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S12S Debug Module (S12SDBGV2)
6.3.2.8.2
Debug Comparator Address High Register (DBGXAH)
Address: 0x0029
R
7
6
5
4
3
2
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
1
0
Bit 17
Bit 16
0
0
= Unimplemented or Reserved
Figure 6-16. Debug Comparator Address High Register (DBGXAH)
The DBGC1_COMRV bits determine which comparator address registers are visible in the 8-byte window
from 0x0028 to 0x002F as shown in Table 6-24.
Table 6-24. Comparator Address Register Visibility
COMRV
Visible Comparator
00
DBGAAH, DBGAAM, DBGAAL
01
DBGBAH, DBGBAM, DBGBAL
10
DBGCAH, DBGCAM, DBGCAL
11
None
Read: Anytime. See Table 6-24 for visible register encoding.
Write: If DBG not armed. See Table 6-24 for visible register encoding.
Table 6-25. DBGXAH Field Descriptions
Field
Description
1–0
Bit[17:16]
Comparator Address High Compare Bits — The Comparator address high compare bits control whether the
selected comparator compares the address bus bits [17:16] to a logic one or logic zero.
0 Compare corresponding address bit to a logic zero
1 Compare corresponding address bit to a logic one
6.3.2.8.3
Debug Comparator Address Mid Register (DBGXAM)
Address: 0x002A
R
W
Reset
7
6
5
4
3
2
1
0
Bit 15
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
0
0
0
0
0
0
0
0
Figure 6-17. Debug Comparator Address Mid Register (DBGXAM)
Read: Anytime. See Table 6-24 for visible register encoding.
Write: If DBG not armed. See Table 6-24 for visible register encoding.
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S12S Debug Module (S12SDBGV2)
Table 6-26. DBGXAM Field Descriptions
Field
7–0
Bit[15:8]
Description
Comparator Address Mid Compare Bits — The Comparator address mid compare bits control whether the
selected comparator compares the address bus bits [15:8] to a logic one or logic zero.
0 Compare corresponding address bit to a logic zero
1 Compare corresponding address bit to a logic one
6.3.2.8.4
Debug Comparator Address Low Register (DBGXAL)
Address: 0x002B
R
W
Reset
7
6
5
4
3
2
1
0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
Figure 6-18. Debug Comparator Address Low Register (DBGXAL)
Read: Anytime. See Table 6-24 for visible register encoding.
Write: If DBG not armed. See Table 6-24 for visible register encoding.
Table 6-27. DBGXAL Field Descriptions
Field
7–0
Bits[7:0]
Description
Comparator Address Low Compare Bits — The Comparator address low compare bits control whether the
selected comparator compares the address bus bits [7:0] to a logic one or logic zero.
0 Compare corresponding address bit to a logic zero
1 Compare corresponding address bit to a logic one
6.3.2.8.5
Debug Comparator Data High Register (DBGADH)
Address: 0x002C
R
W
Reset
7
6
5
4
3
2
1
0
Bit 15
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
0
0
0
0
0
0
0
0
Figure 6-19. Debug Comparator Data High Register (DBGADH)
Read: If COMRV[1:0] = 00
Write: If COMRV[1:0] = 00 and DBG not armed.
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S12S Debug Module (S12SDBGV2)
Table 6-28. DBGADH Field Descriptions
Field
Description
7–0
Bits[15:8]
Comparator Data High Compare Bits— The Comparator data high compare bits control whether the selected
comparator compares the data bus bits [15:8] to a logic one or logic zero. The comparator data compare bits are
only used in comparison if the corresponding data mask bit is logic 1. This register is available only for
comparator A. Data bus comparisons are only performed if the TAG bit in DBGACTL is clear.
0 Compare corresponding data bit to a logic zero
1 Compare corresponding data bit to a logic one
6.3.2.8.6
Debug Comparator Data Low Register (DBGADL)
Address: 0x002D
R
W
Reset
7
6
5
4
3
2
1
0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
Figure 6-20. Debug Comparator Data Low Register (DBGADL)
Read: If COMRV[1:0] = 00
Write: If COMRV[1:0] = 00 and DBG not armed.
Table 6-29. DBGADL Field Descriptions
Field
Description
7–0
Bits[7:0]
Comparator Data Low Compare Bits — The Comparator data low compare bits control whether the selected
comparator compares the data bus bits [7:0] to a logic one or logic zero. The comparator data compare bits are
only used in comparison if the corresponding data mask bit is logic 1. This register is available only for
comparator A. Data bus comparisons are only performed if the TAG bit in DBGACTL is clear
0 Compare corresponding data bit to a logic zero
1 Compare corresponding data bit to a logic one
6.3.2.8.7
Debug Comparator Data High Mask Register (DBGADHM)
Address: 0x002E
R
W
Reset
7
6
5
4
3
2
1
0
Bit 15
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
0
0
0
0
0
0
0
0
Figure 6-21. Debug Comparator Data High Mask Register (DBGADHM)
Read: If COMRV[1:0] = 00
Write: If COMRV[1:0] = 00 and DBG not armed.
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S12S Debug Module (S12SDBGV2)
Table 6-30. DBGADHM Field Descriptions
Field
Description
7–0
Bits[15:8]
Comparator Data High Mask Bits — The Comparator data high mask bits control whether the selected
comparator compares the data bus bits [15:8] to the corresponding comparator data compare bits. Data bus
comparisons are only performed if the TAG bit in DBGACTL is clear
0 Do not compare corresponding data bit Any value of corresponding data bit allows match.
1 Compare corresponding data bit
6.3.2.8.8
Debug Comparator Data Low Mask Register (DBGADLM)
Address: 0x002F
R
W
Reset
7
6
5
4
3
2
1
0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
Figure 6-22. Debug Comparator Data Low Mask Register (DBGADLM)
Read: If COMRV[1:0] = 00
Write: If COMRV[1:0] = 00 and DBG not armed.
Table 6-31. DBGADLM Field Descriptions
Field
7–0
Bits[7:0]
6.4
Description
Comparator Data Low Mask Bits — The Comparator data low mask bits control whether the selected
comparator compares the data bus bits [7:0] to the corresponding comparator data compare bits. Data bus
comparisons are only performed if the TAG bit in DBGACTL is clear
0 Do not compare corresponding data bit. Any value of corresponding data bit allows match
1 Compare corresponding data bit
Functional Description
This section provides a complete functional description of the DBG module. If the part is in secure mode,
the DBG module can generate breakpoints but tracing is not possible.
6.4.1
S12SDBG Operation
Arming the DBG module by setting ARM in DBGC1 allows triggering the state sequencer, storing of data
in the trace buffer and generation of breakpoints to the CPU. The DBG module is made up of four main
blocks, the comparators, control logic, the state sequencer, and the trace buffer.
The comparators monitor the bus activity of the CPU. All comparators can be configured to monitor
address bus activity. Comparator A can also be configured to monitor databus activity and mask out
individual data bus bits during a compare. Comparators can be configured to use R/W and word/byte
access qualification in the comparison. A match with a comparator register value can initiate a state
sequencer transition to another state (see Figure 6-24). Either forced or tagged matches are possible. Using
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S12S Debug Module (S12SDBGV2)
a forced match, a state sequencer transition can occur immediately on a successful match of system busses
and comparator registers. Whilst tagging, at a comparator match, the instruction opcode is tagged and only
if the instruction reaches the execution stage of the instruction queue can a state sequencer transition occur.
In the case of a transition to Final State, bus tracing is triggered and/or a breakpoint can be generated.
A state sequencer transition to final state (with associated breakpoint, if enabled) can be initiated by
writing to the TRIG bit in the DBGC1 control register.
The trace buffer is visible through a 2-byte window in the register address map and must be read out using
standard 16-bit word reads.
TAGS
TAGHITS
BREAKPOINT REQUESTS
TO CPU
COMPARATOR A
COMPARATOR B
COMPARATOR C
COMPARATOR
MATCH CONTROL
CPU BUS
BUS INTERFACE
SECURE
MATCH0
MATCH1
TAG &
MATCH
CONTROL
LOGIC
TRANSITION
STATE
STATE SEQUENCER
STATE
MATCH2
TRACE
CONTROL
TRIGGER
TRACE BUFFER
READ TRACE DATA (DBG READ DATA BUS)
Figure 6-23. DBG Overview
6.4.2
Comparator Modes
The DBG contains three comparators, A, B and C. Each comparator compares the system address bus with
the address stored in DBGXAH, DBGXAM, and DBGXAL. Furthermore, comparator A also compares
the data buses to the data stored in DBGADH, DBGADL and allows masking of individual data bus bits.
All comparators are disabled in BDM and during BDM accesses.
The comparator match control logic (see Figure 6-23) configures comparators to monitor the buses for an
exact address or an address range, whereby either an access inside or outside the specified range generates
a match condition. The comparator configuration is controlled by the control register contents and the
range control by the DBGC2 contents.
A match can initiate a transition to another state sequencer state (see 6.4.4”). The comparator control
register also allows the type of access to be included in the comparison through the use of the RWE, RW,
SZE, and SZ bits. The RWE bit controls whether read or write comparison is enabled for the associated
comparator and the RW bit selects either a read or write access for a valid match. Similarly the SZE and
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SZ bits allow the size of access (word or byte) to be considered in the compare. Only comparators A and
B feature SZE and SZ.
The TAG bit in each comparator control register is used to determine the match condition. By setting TAG,
the comparator qualifies a match with the output of opcode tracking logic and a state sequencer transition
occurs when the tagged instruction reaches the CPU execution stage. Whilst tagging the RW, RWE, SZE,
and SZ bits and the comparator data registers are ignored; the comparator address register must be loaded
with the exact opcode address.
If the TAG bit is clear (forced type match) a comparator match is generated when the selected address
appears on the system address bus. If the selected address is an opcode address, the match is generated
when the opcode is fetched from the memory, which precedes the instruction execution by an indefinite
number of cycles due to instruction pipelining. For a comparator match of an opcode at an odd address
when TAG = 0, the corresponding even address must be contained in the comparator register. Thus for an
opcode at odd address (n), the comparator register must contain address (n–1).
Once a successful comparator match has occurred, the condition that caused the original match is not
verified again on subsequent matches. Thus if a particular data value is verified at a given address, this
address may not still contain that data value when a subsequent match occurs.
Match[0, 1, 2] map directly to Comparators [A, B, C] respectively, except in range modes (see 6.3.2.4).
Comparator channel priority rules are described in the priority section (6.4.3.4).
6.4.2.1
Single Address Comparator Match
With range comparisons disabled, the match condition is an exact equivalence of address bus with the
value stored in the comparator address registers. Further qualification of the type of access (R/W,
word/byte) and databus contents is possible, depending on comparator channel.
6.4.2.1.1
Comparator C
Comparator C offers only address and direction (R/W) comparison. The exact address is compared, thus
with the comparator address register loaded with address (n) a word access of address (n–1) also accesses
(n) but does not cause a match.
Table 6-32. Comparator C Access Considerations
Condition For Valid Match
Read and write accesses of ADDR[n]
Write accesses of ADDR[n]
Comp C Address RWE
(1)
ADDR[n]
ADDR[n]
RW
0
X
LDAA ADDR[n]
STAA #$BYTE ADDR[n]
1
0
STAA #$BYTE ADDR[n]
Read accesses of ADDR[n]
ADDR[n]
1
1
1. A word access of ADDR[n-1] also accesses ADDR[n] but does not generate a match.
The comparator address register must contain the exact address from the code.
6.4.2.1.2
Examples
LDAA #$BYTE ADDR[n]
Comparator B
Comparator B offers address, direction (R/W) and access size (word/byte) comparison. If the SZE bit is
set the access size (word or byte) is compared with the SZ bit value such that only the specified size of
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access causes a match. Thus if configured for a byte access of a particular address, a word access covering
the same address does not lead to match.
Assuming the access direction is not qualified (RWE=0), for simplicity, the size access considerations are
shown in Table 6-33.
Table 6-33. Comparator B Access Size Considerations
Condition For Valid Match
Comp B Address RWE
Word and byte accesses of ADDR[n]
ADDR[n]
(1)
SZE
SZ8
Examples
0
0
X
MOVB #$BYTE ADDR[n]
MOVW #$WORD ADDR[n]
Word accesses of ADDR[n] only
ADDR[n]
0
1
0
MOVW #$WORD ADDR[n]
LDD ADDR[n]
Byte accesses of ADDR[n] only
ADDR[n]
0
1
1
MOVB #$BYTE ADDR[n]
LDAB ADDR[n]
1. A word access of ADDR[n-1] also accesses ADDR[n] but does not generate a match.
The comparator address register must contain the exact address from the code.
Access direction can also be used to qualify a match for Comparator B in the same way as described for
Comparator C in Table 6-32.
6.4.2.1.3
Comparator A
Comparator A offers address, direction (R/W), access size (word/byte) and data bus comparison.
Table 6-34 lists access considerations with data bus comparison. On word accesses the data byte of the
lower address is mapped to DBGADH. Access direction can also be used to qualify a match for
Comparator A in the same way as described for Comparator C in Table 6-32.
Table 6-34. Comparator A Matches When Accessing ADDR[n]
SZE
SZ
DBGADHM,
DBGADLM
Access
DH=DBGADH, DL=DBGADL
0
X
$0000
Byte
Word
No databus comparison
0
X
$FF00
Byte, data(ADDR[n])=DH
Word, data(ADDR[n])=DH, data(ADDR[n+1])=X
Match data( ADDR[n])
0
X
$00FF
Word, data(ADDR[n])=X, data(ADDR[n+1])=DL
Match data( ADDR[n+1])
0
X
$00FF
Byte, data(ADDR[n])=X, data(ADDR[n+1])=DL
Possible unintended match
0
X
$FFFF
Word, data(ADDR[n])=DH, data(ADDR[n+1])=DL
Match data( ADDR[n], ADDR[n+1])
0
X
$FFFF
Byte, data(ADDR[n])=DH, data(ADDR[n+1])=DL
Possible unintended match
1
0
$0000
Word
No databus comparison
1
0
$00FF
Word, data(ADDR[n])=X, data(ADDR[n+1])=DL
Match only data at ADDR[n+1]
1
0
$FF00
Word, data(ADDR[n])=DH, data(ADDR[n+1])=X
Match only data at ADDR[n]
1
0
$FFFF
Word, data(ADDR[n])=DH, data(ADDR[n+1])=DL
Match data at ADDR[n] & ADDR[n+1]
1
1
$0000
Byte
No databus comparison
1
1
$FF00
Byte, data(ADDR[n])=DH
Match data at ADDR[n]
Comment
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6.4.2.1.4
Comparator A Data Bus Comparison NDB Dependency
Comparator A features an NDB control bit, which allows data bus comparators to be configured to either
trigger on equivalence or trigger on difference. This allows monitoring of a difference in the contents of
an address location from an expected value.
When matching on an equivalence (NDB=0), each individual data bus bit position can be masked out by
clearing the corresponding mask bit (DBGADHM/DBGADLM) so that it is ignored in the comparison. A
match occurs when all data bus bits with corresponding mask bits set are equivalent. If all mask register
bits are clear, then a match is based on the address bus only, the data bus is ignored.
When matching on a difference, mask bits can be cleared to ignore bit positions. A match occurs when any
data bus bit with corresponding mask bit set is different. Clearing all mask bits, causes all bits to be ignored
and prevents a match because no difference can be detected. In this case address bus equivalence does not
cause a match.
Table 6-35. NDB and MASK bit dependency
6.4.2.2
NDB
DBGADHM[n] /
DBGADLM[n]
Comment
0
0
Do not compare data bus bit.
0
1
Compare data bus bit. Match on equivalence.
1
0
Do not compare data bus bit.
1
1
Compare data bus bit. Match on difference.
Range Comparisons
Using the AB comparator pair for a range comparison, the data bus can also be used for qualification by
using the comparator A data registers. Furthermore the DBGACTL RW and RWE bits can be used to
qualify the range comparison on either a read or a write access. The corresponding DBGBCTL bits are
ignored. The SZE and SZ control bits are ignored in range mode. The comparator A TAG bit is used to tag
range comparisons. The comparator B TAG bit is ignored in range modes. In order for a range comparison
using comparators A and B, both COMPEA and COMPEB must be set; to disable range comparisons both
must be cleared. The comparator A BRK bit is used to for the AB range, the comparator B BRK bit is
ignored in range mode.
When configured for range comparisons and tagging, the ranges are accurate only to word boundaries.
6.4.2.2.1
Inside Range (CompA_Addr ≤ address ≤ CompB_Addr)
In the Inside Range comparator mode, comparator pair A and B can be configured for range comparisons.
This configuration depends upon the control register (DBGC2). The match condition requires that a valid
match for both comparators happens on the same bus cycle. A match condition on only one comparator is
not valid. An aligned word access which straddles the range boundary is valid only if the aligned address
is inside the range.
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6.4.2.2.2
Outside Range (address < CompA_Addr or address > CompB_Addr)
In the Outside Range comparator mode, comparator pair A and B can be configured for range comparisons.
A single match condition on either of the comparators is recognized as valid. An aligned word access
which straddles the range boundary is valid only if the aligned address is outside the range.
Outside range mode in combination with tagging can be used to detect if the opcode fetches are from an
unexpected range. In forced match mode the outside range match would typically be activated at any
interrupt vector fetch or register access. This can be avoided by setting the upper range limit to $3FFFF or
lower range limit to $00000 respectively.
6.4.3
Match Modes (Forced or Tagged)
Match modes are used as qualifiers for a state sequencer change of state. The Comparator control register
TAG bits select the match mode. The modes are described in the following sections.
6.4.3.1
Forced Match
When configured for forced matching, a comparator channel match can immediately initiate a transition
to the next state sequencer state whereby the corresponding flags in DBGSR are set. The state control
register for the current state determines the next state. Forced matches are typically generated 2-3 bus
cycles after the final matching address bus cycle, independent of comparator RWE/RW settings.
Furthermore since opcode fetches occur several cycles before the opcode execution a forced match of an
opcode address typically precedes a tagged match at the same address.
6.4.3.2
Tagged Match
If a CPU taghit occurs a transition to another state sequencer state is initiated and the corresponding
DBGSR flags are set. For a comparator related taghit to occur, the DBG must first attach tags to
instructions as they are fetched from memory. When the tagged instruction reaches the execution stage of
the instruction queue a taghit is generated by the CPU. This can initiate a state sequencer transition.
6.4.3.3
Immediate Trigger
Independent of comparator matches it is possible to initiate a tracing session and/or breakpoint by writing
to the TRIG bit in DBGC1. If configured for begin aligned tracing, this triggers the state sequencer into
the Final State, if configured for end alignment, setting the TRIG bit disarms the module, ending the
session and issues a forced breakpoint request to the CPU.
It is possible to set both TRIG and ARM simultaneously to generate an immediate trigger, independent of
the current state of ARM.
6.4.3.4
Channel Priorities
In case of simultaneous matches the priority is resolved according to Table 6-36. The lower priority is
suppressed. It is thus possible to miss a lower priority match if it occurs simultaneously with a higher
priority. The priorities described in Table 6-36 dictate that in the case of simultaneous matches, the match
pointing to final state has highest priority followed by the lower channel number (0,1,2).
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Table 6-36. Channel Priorities
Priority
Source
Action
Highest
TRIG
Enter Final State
Channel pointing to Final State
Transition to next state as defined by state control registers
Match0 (force or tag hit)
Transition to next state as defined by state control registers
Match1 (force or tag hit)
Transition to next state as defined by state control registers
Match2 (force or tag hit)
Transition to next state as defined by state control registers
Lowest
6.4.4
State Sequence Control
ARM = 0
State 0
(Disarmed)
ARM = 1
State1
State2
ARM = 0
Session Complete
(Disarm)
Final State
State3
ARM = 0
Figure 6-24. State Sequencer Diagram
The state sequencer allows a defined sequence of events to provide a trigger point for tracing of data in the
trace buffer. Once the DBG module has been armed by setting the ARM bit in the DBGC1 register, then
state1 of the state sequencer is entered. Further transitions between the states are then controlled by the
state control registers and channel matches. From Final State the only permitted transition is back to the
disarmed state0. Transition between any of the states 1 to 3 is not restricted. Each transition updates the
SSF[2:0] flags in DBGSR accordingly to indicate the current state.
Alternatively writing to the TRIG bit in DBGSC1, provides an immediate trigger independent of
comparator matches.
Independent of the state sequencer, each comparator channel can be individually configured to generate an
immediate breakpoint when a match occurs through the use of the BRK bits in the DBGxCTL registers.
Thus it is possible to generate an immediate breakpoint on selected channels, whilst a state sequencer
transition can be initiated by a match on other channels. If a debug session is ended by a match on a channel
the state sequencer transitions through Final State for a clock cycle to state0. This is independent of tracing
and breakpoint activity, thus with tracing and breakpoints disabled, the state sequencer enters state0 and
the debug module is disarmed.
6.4.4.1
Final State
On entering Final State a trigger may be issued to the trace buffer according to the trace alignment control
as defined by the TALIGN bit (see 6.3.2.3”). If the TSOURCE bit in DBGTCR is clear then the trace buffer
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is disabled and the transition to Final State can only generate a breakpoint request. In this case or upon
completion of a tracing session when tracing is enabled, the ARM bit in the DBGC1 register is cleared,
returning the module to the disarmed state0. If tracing is enabled a breakpoint request can occur at the end
of the tracing session. If neither tracing nor breakpoints are enabled then when the final state is reached it
returns automatically to state0 and the debug module is disarmed.
6.4.5
Trace Buffer Operation
The trace buffer is a 64 lines deep by 20-bits wide RAM array. The DBG module stores trace information
in the RAM array in a circular buffer format. The system accesses the RAM array through a register
window (DBGTBH:DBGTBL) using 16-bit wide word accesses. After each complete 20-bit trace buffer
line is read, an internal pointer into the RAM increments so that the next read receives fresh information.
Data is stored in the format shown in Table 6-37 and Table 6-40. After each store the counter register
DBGCNT is incremented. Tracing of CPU activity is disabled when the BDM is active. Reading the trace
buffer whilst the DBG is armed returns invalid data and the trace buffer pointer is not incremented.
6.4.5.1
Trace Trigger Alignment
Using the TALIGN bit (see 6.3.2.3) it is possible to align the trigger with the end or the beginning of a
tracing session.
If end alignment is selected, tracing begins when the ARM bit in DBGC1 is set and State1 is entered; the
transition to Final State signals the end of the tracing session. Tracing with Begin-Trigger starts at the
opcode of the trigger. Using end alignment or when the tracing is initiated by writing to the TRIG bit whilst
configured for begin alignment, tracing starts in the second cycle after the DBGC1 write cycle.
6.4.5.1.1
Storing with Begin Trigger Alignment
Storing with begin alignment, data is not stored in the Trace Buffer until the Final State is entered. Once
the trigger condition is met the DBG module remains armed until 64 lines are stored in the Trace Buffer.
If the trigger is at the address of the change-of-flow instruction the change of flow associated with the
trigger is stored in the Trace Buffer. Using begin alignment together with tagging, if the tagged instruction
is about to be executed then the trace is started. Upon completion of the tracing session the breakpoint is
generated, thus the breakpoint does not occur at the tagged instruction boundary.
6.4.5.1.2
Storing with End Trigger Alignment
Storing with end alignment, data is stored in the Trace Buffer until the Final State is entered, at which point
the DBG module becomes disarmed and no more data is stored. If the trigger is at the address of a change
of flow instruction, the trigger event is not stored in the Trace Buffer. If all trace buffer lines have been
used before a trigger event occurrs then the trace continues at the first line, overwriting the oldest entries.
6.4.5.2
Trace Modes
Four trace modes are available. The mode is selected using the TRCMOD bits in the DBGTCR register.
Tracing is enabled using the TSOURCE bit in the DBGTCR register. The modes are described in the
following subsections.
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6.4.5.2.1
Normal Mode
In Normal Mode, change of flow (COF) program counter (PC) addresses are stored.
COF addresses are defined as follows:
• Source address of taken conditional branches (long, short, bit-conditional, and loop primitives)
• Destination address of indexed JMP, JSR, and CALL instruction
• Destination address of RTI, RTS, and RTC instructions
• Vector address of interrupts, except for BDM vectors
LBRA, BRA, BSR, BGND as well as non-indexed JMP, JSR, and CALL instructions are not classified as
change of flow and are not stored in the trace buffer.
Stored information includes the full 18-bit address bus and information bits, which contains a
source/destination bit to indicate whether the stored address was a source address or destination address.
NOTE
When a COF instruction with destination address is executed, the
destination address is stored to the trace buffer on instruction completion,
indicating the COF has taken place. If an interrupt occurs simultaneously
then the next instruction carried out is actually from the interrupt service
routine. The instruction at the destination address of the original program
flow gets executed after the interrupt service routine.
In the following example an IRQ interrupt occurs during execution of the
indexed JMP at address MARK1. The BRN at the destination (SUB_1) is
not executed until after the IRQ service routine but the destination address
is entered into the trace buffer to indicate that the indexed JMP COF has
taken place.
MARK1
MARK2
LDX
JMP
NOP
#SUB_1
0,X
SUB_1
BRN
*
ADDR1
NOP
DBNE
A,PART5
IRQ_ISR
LDAB
STAB
RTI
#$F0
VAR_C1
; IRQ interrupt occurs during execution of this
;
; JMP Destination address TRACE BUFFER ENTRY 1
; RTI Destination address TRACE BUFFER ENTRY 3
;
; Source address TRACE BUFFER ENTRY 4
; IRQ Vector $FFF2 = TRACE BUFFER ENTRY 2
;
The execution flow taking into account the IRQ is as follows
MARK1
IRQ_ISR
SUB_1
ADDR1
LDX
JMP
LDAB
STAB
RTI
BRN
NOP
DBNE
#SUB_1
0,X
#$F0
VAR_C1
;
;
;
*
A,PART5
;
;
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6.4.5.2.2
Loop1 Mode
Loop1 Mode, similarly to Normal Mode also stores only COF address information to the trace buffer, it
however allows the filtering out of redundant information.
The intent of Loop1 Mode is to prevent the Trace Buffer from being filled entirely with duplicate
information from a looping construct such as delays using the DBNE instruction or polling loops using
BRSET/BRCLR instructions. Immediately after address information is placed in the Trace Buffer, the
DBG module writes this value into a background register. This prevents consecutive duplicate address
entries in the Trace Buffer resulting from repeated branches.
Loop1 Mode only inhibits consecutive duplicate source address entries that would typically be stored in
most tight looping constructs. It does not inhibit repeated entries of destination addresses or vector
addresses, since repeated entries of these would most likely indicate a bug in the user’s code that the DBG
module is designed to help find.
6.4.5.2.3
Detail Mode
In Detail Mode, address and data for all memory and register accesses is stored in the trace buffer. This
mode is intended to supply additional information on indexed, indirect addressing modes where storing
only the destination address would not provide all information required for a user to determine where the
code is in error. This mode also features information bit storage to the trace buffer, for each address byte
storage. The information bits indicate the size of access (word or byte) and the type of access (read or
write).
When tracing in Detail Mode, all cycles are traced except those when the CPU is either in a free or opcode
fetch cycle.
6.4.5.2.4
Compressed Pure PC Mode
In Compressed Pure PC Mode, the PC addresses of all executed opcodes, including illegal opcodes are
stored. A compressed storage format is used to increase the effective depth of the trace buffer. This is
achieved by storing the lower order bits each time and using 2 information bits to indicate if a 64 byte
boundary has been crossed, in which case the full PC is stored.
Each Trace Buffer row consists of 2 information bits and 18 PC address bits
NOTE:
When tracing is terminated using forced breakpoints, latency in breakpoint
generation means that opcodes following the opcode causing the breakpoint
can be stored to the trace buffer. The number of opcodes is dependent on
program flow. This can be avoided by using tagged breakpoints.
6.4.5.3
Trace Buffer Organization (Normal, Loop1, Detail modes)
ADRH, ADRM, ADRL denote address high, middle and low byte respectively. The numerical suffix refers
to the tracing count. The information format for Loop1 and Normal modes is identical. In Detail mode, the
address and data for each entry are stored on consecutive lines, thus the maximum number of entries is 32.
In this case DBGCNT bits are incremented twice, once for the address line and once for the data line, on
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each trace buffer entry. In Detail mode CINF comprises of R/W and size access information (CRW and
CSZ respectively).
Single byte data accesses in Detail Mode are always stored to the low byte of the trace buffer (DATAL)
and the high byte is cleared. When tracing word accesses, the byte at the lower address is always stored to
trace buffer byte1 and the byte at the higher address is stored to byte0.
Table 6-37. Trace Buffer Organization (Normal,Loop1,Detail modes)
Entry 1
Detail Mode
8-bits
8-bits
Field 2
Field 1
Field 0
CINF1,ADRH1
ADRM1
ADRL1
0
DATAH1
DATAL1
CINF2,ADRH2
ADRM2
ADRL2
0
DATAH2
DATAL2
Entry 1
PCH1
PCM1
PCL1
Entry 2
PCH2
PCM2
PCL2
Entry 2
Normal/Loop1
Modes
6.4.5.3.1
4-bits
Entry
Number
Mode
Information Bit Organization
The format of the bits is dependent upon the active trace mode as described below.
Field2 Bits in Detail Mode
Bit 3
Bit 2
CSZ
CRW
Bit 1
Bit 0
ADDR[17] ADDR[16]
Figure 6-25. Field2 Bits in Detail Mode
In Detail Mode the CSZ and CRW bits indicate the type of access being made by the CPU.
Table 6-38. Field Descriptions
Bit
Description
3
CSZ
Access Type Indicator— This bit indicates if the access was a byte or word size when tracing in Detail Mode
0 Word Access
1 Byte Access
2
CRW
Read Write Indicator — This bit indicates if the corresponding stored address corresponds to a read or write
access when tracing in Detail Mode.
0 Write Access
1 Read Access
1
ADDR[17]
Address Bus bit 17— Corresponds to system address bus bit 17.
0
ADDR[16]
Address Bus bit 16— Corresponds to system address bus bit 16.
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Field2 Bits in Normal and Loop1 Modes
Bit 3
Bit 2
Bit 1
Bit 0
CSD
CVA
PC17
PC16
Figure 6-26. Information Bits PCH
Table 6-39. PCH Field Descriptions
Bit
Description
3
CSD
Source Destination Indicator — In Normal and Loop1 mode this bit indicates if the corresponding stored
address is a source or destination address. This bit has no meaning in Compressed Pure PC mode.
0 Source Address
1 Destination Address
2
CVA
Vector Indicator — In Normal and Loop1 mode this bit indicates if the corresponding stored address is a vector
address. Vector addresses are destination addresses, thus if CVA is set, then the corresponding CSD is also set.
This bit has no meaning in Compressed Pure PC mode.
0 Non-Vector Destination Address
1 Vector Destination Address
1
PC17
Program Counter bit 17— In Normal and Loop1 mode this bit corresponds to program counter bit 17.
0
PC16
Program Counter bit 16— In Normal and Loop1 mode this bit corresponds to program counter bit 16.
6.4.5.4
Trace Buffer Organization (Compressed Pure PC mode)
Table 6-40. Trace Buffer Organization Example (Compressed PurePC mode)
2-bits
Line
Number Field 3
Mode
Compressed
Pure PC Mode
6-bits
Field 2
6-bits
6-bits
Field 1
Field 0
Line 1
00
PC1 (Initial 18-bit PC Base Address)
Line 2
11
PC4
PC3
PC2
Line 3
01
0
0
PC5
Line 4
00
Line 5
10
Line 6
00
PC6 (New 18-bit PC Base Address)
0
PC8
PC7
PC9 (New 18-bit PC Base Address)
NOTE
Configured for end aligned triggering in compressed PurePC mode, then
after rollover it is possible that the oldest base address is overwritten. In this
case all entries between the pointer and the next base address have lost their
base address following rollover. For example in Table 6-40 if one line of
rollover has occurred, Line 1, PC1, is overwritten with a new entry. Thus the
entries on Lines 2 and 3 have lost their base address. For reconstruction of
program flow the first base address following the pointer must be used, in
the example, Line 4. The pointer points to the oldest entry, Line 2.
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Field3 Bits in Compressed Pure PC Modes
Table 6-41. Compressed Pure PC Mode Field 3 Information Bit Encoding
INF1
INF0
TRACE BUFFER ROW CONTENT
0
0
Base PC address TB[17:0] contains a full PC[17:0] value
0
1
Trace Buffer[5:0] contain incremental PC relative to base address zero value
1
0
Trace Buffer[11:0] contain next 2 incremental PCs relative to base address zero value
1
1
Trace Buffer[17:0] contain next 3 incremental PCs relative to base address zero value
Each time that PC[17:6] differs from the previous base PC[17:6], then a new base address is stored. The
base address zero value is the lowest address in the 64 address range
The first line of the trace buffer always gets a base PC address, this applies also on rollover.
6.4.5.5
Reading Data from Trace Buffer
The data stored in the Trace Buffer can be read provided the DBG module is not armed, is configured for
tracing (TSOURCE bit is set) and the system not secured. When the ARM bit is written to 1 the trace buffer
is locked to prevent reading. The trace buffer can only be unlocked for reading by a single aligned word
write to DBGTB when the module is disarmed.
The Trace Buffer can only be read through the DBGTB register using aligned word reads, any byte or
misaligned reads return 0 and do not cause the trace buffer pointer to increment to the next trace buffer
address. The Trace Buffer data is read out first-in first-out. By reading CNT in DBGCNT the number of
valid lines can be determined. DBGCNT does not decrement as data is read.
Whilst reading an internal pointer is used to determine the next line to be read. After a tracing session, the
pointer points to the oldest data entry, thus if no rollover has occurred, the pointer points to line0, otherwise
it points to the line with the oldest entry. In compressed Pure PC mode on rollover the line with the oldest
data entry may also contain newer data entries in fields 0 and 1. Thus if rollover is indicated by the TBF
bit, the line status must be decoded using the INF bits in field3 of that line. If both INF bits are clear then
the line contains only entries from before the last rollover.
If INF0=1 then field 0 contains post rollover data but fields 1 and 2 contain pre rollover data.
If INF1=1 then fields 0 and 1 contain post rollover data but field 2 contains pre rollover data.
The pointer is initialized by each aligned write to DBGTBH to point to the oldest data again. This enables
an interrupted trace buffer read sequence to be easily restarted from the oldest data entry.
The least significant word of line is read out first. This corresponds to the fields 1 and 0 of Table 6-37. The
next word read returns field 2 in the least significant bits [3:0] and “0” for bits [15:4].
Reading the Trace Buffer while the DBG module is armed returns invalid data and no shifting of the RAM
pointer occurs.
6.4.5.6
Trace Buffer Reset State
The Trace Buffer contents and DBGCNT bits are not initialized by a system reset. Thus should a system
reset occur, the trace session information from immediately before the reset occurred can be read out and
the number of valid lines in the trace buffer is indicated by DBGCNT. The internal pointer to the current
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S12S Debug Module (S12SDBGV2)
trace buffer address is initialized by unlocking the trace buffer and points to the oldest valid data even if a
reset occurred during the tracing session. To read the trace buffer after a reset, TSOURCE must be set,
otherwise the trace buffer reads as all zeroes. Generally debugging occurrences of system resets is best
handled using end trigger alignment since the reset may occur before the trace trigger, which in the begin
trigger alignment case means no information would be stored in the trace buffer.
The Trace Buffer contents and DBGCNT bits are undefined following a POR.
NOTE
An external pin RESET that occurs simultaneous to a trace buffer entry can,
in very seldom cases, lead to either that entry being corrupted or the first
entry of the session being corrupted. In such cases the other contents of the
trace buffer still contain valid tracing information. The case occurs when the
reset assertion coincides with the trace buffer entry clock edge.
6.4.6
Tagging
A tag follows program information as it advances through the instruction queue. When a tagged instruction
reaches the head of the queue a tag hit occurs and can initiate a state sequencer transition.
Each comparator control register features a TAG bit, which controls whether the comparator match causes
a state sequencer transition immediately or tags the opcode at the matched address. If a comparator is
enabled for tagged comparisons, the address stored in the comparator match address registers must be an
opcode address.
Using Begin trigger together with tagging, if the tagged instruction is about to be executed then the
transition to the next state sequencer state occurs. If the transition is to the Final State, tracing is started.
Only upon completion of the tracing session can a breakpoint be generated. Using End alignment, when
the tagged instruction is about to be executed and the next transition is to Final State then a breakpoint is
generated immediately, before the tagged instruction is carried out.
R/W monitoring, access size (SZ) monitoring and data bus monitoring are not useful if tagging is selected,
since the tag is attached to the opcode at the matched address and is not dependent on the data bus nor on
the type of access. Thus these bits are ignored if tagging is selected.
When configured for range comparisons and tagging, the ranges are accurate only to word boundaries.
Tagging is disabled when the BDM becomes active.
6.4.7
Breakpoints
It is possible to generate breakpoints from channel transitions to final state or using software to write to
the TRIG bit in the DBGC1 register.
6.4.7.1
Breakpoints From Comparator Channels
Breakpoints can be generated when the state sequencer transitions to the Final State. If configured for
tagging, then the breakpoint is generated when the tagged opcode reaches the execution stage of the
instruction queue.
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S12S Debug Module (S12SDBGV2)
If a tracing session is selected by the TSOURCE bit, breakpoints are requested when the tracing session
has completed, thus if Begin aligned triggering is selected, the breakpoint is requested only on completion
of the subsequent trace (see Table 6-42). If no tracing session is selected, breakpoints are requested
immediately.
If the BRK bit is set, then the associated breakpoint is generated immediately independent of tracing
trigger alignment.
Table 6-42. Breakpoint Setup For CPU Breakpoints
BRK
TALIGN
DBGBRK
Breakpoint Alignment
0
0
0
Fill Trace Buffer until trigger then disarm (no breakpoints)
0
0
1
Fill Trace Buffer until trigger, then breakpoint request occurs
0
1
0
Start Trace Buffer at trigger (no breakpoints)
0
1
1
Start Trace Buffer at trigger
A breakpoint request occurs when Trace Buffer is full
1
x
1
Terminate tracing and generate breakpoint immediately on trigger
1
x
0
Terminate tracing immediately on trigger
6.4.7.2
Breakpoints Generated Via The TRIG Bit
If a TRIG triggers occur, the Final State is entered whereby tracing trigger alignment is defined by the
TALIGN bit. If a tracing session is selected by the TSOURCE bit, breakpoints are requested when the
tracing session has completed, thus if Begin aligned triggering is selected, the breakpoint is requested only
on completion of the subsequent trace (see Table 6-42). If no tracing session is selected, breakpoints are
requested immediately. TRIG breakpoints are possible with a single write to DBGC1, setting ARM and
TRIG simultaneously.
6.4.7.3
Breakpoint Priorities
If a TRIG trigger occurs after Begin aligned tracing has already started, then the TRIG no longer has an
effect. When the associated tracing session is complete, the breakpoint occurs. Similarly if a TRIG is
followed by a subsequent comparator channel match, it has no effect, since tracing has already started.
If a forced SWI breakpoint coincides with a BGND in user code with BDM enabled, then the BDM is
activated by the BGND and the breakpoint to SWI is suppressed.
6.4.7.3.1
DBG Breakpoint Priorities And BDM Interfacing
Breakpoint operation is dependent on the state of the BDM module. If the BDM module is active, the CPU
is executing out of BDM firmware, thus comparator matches and associated breakpoints are disabled. In
addition, while executing a BDM TRACE command, tagging into BDM is disabled. If BDM is not active,
the breakpoint gives priority to BDM requests over SWI requests if the breakpoint happens to coincide
with a SWI instruction in user code. On returning from BDM, the SWI from user code gets executed.
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Table 6-43. Breakpoint Mapping Summary
DBGBRK
BDM Bit
(DBGC1[4])
BDM
Enabled
BDM
Active
Breakpoint
Mapping
0
X
X
X
No Breakpoint
1
0
X
0
Breakpoint to SWI
X
X
1
1
No Breakpoint
1
1
0
X
Breakpoint to SWI
1
1
1
0
Breakpoint to BDM
BDM cannot be entered from a breakpoint unless the ENABLE bit is set in the BDM. If entry to BDM via
a BGND instruction is attempted and the ENABLE bit in the BDM is cleared, the CPU actually executes
the BDM firmware code, checks the ENABLE and returns if ENABLE is not set. If not serviced by the
monitor then the breakpoint is re-asserted when the BDM returns to normal CPU flow.
If the comparator register contents coincide with the SWI/BDM vector address then an SWI in user code
could coincide with a DBG breakpoint. The CPU ensures that BDM requests have a higher priority than
SWI requests. Returning from the BDM/SWI service routine care must be taken to avoid a repeated
breakpoint at the same address.
Should a tagged or forced breakpoint coincide with a BGND in user code, then the instruction that follows
the BGND instruction is the first instruction executed when normal program execution resumes.
NOTE
When program control returns from a tagged breakpoint using an RTI or
BDM GO command without program counter modification it returns to the
instruction whose tag generated the breakpoint. To avoid a repeated
breakpoint at the same location reconfigure the DBG module in the SWI
routine, if configured for an SWI breakpoint, or over the BDM interface by
executing a TRACE command before the GO to increment the program flow
past the tagged instruction.
6.5
6.5.1
Application Information
State Machine scenarios
Defining the state control registers as SCR1,SCR2, SCR3 and M0,M1,M2 as matches on channels 0,1,2
respectively. SCR encoding supported by S12SDBGV1 are shown in black. SCR encoding supported only
in S12SDBGV2 are shown in red. For backwards compatibility the new scenarios use a 4th bit in each SCR
register. Thus the existing encoding for SCRx[2:0] is not changed.
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6.5.2
Scenario 1
A trigger is generated if a given sequence of 3 code events is executed.
Figure 6-27. Scenario 1
SCR2=0010
SCR1=0011
State1
M1
SCR3=0111
M2
State2
State3
M0
Final State
Scenario 1 is possible with S12SDBGV1 SCR encoding
6.5.3
Scenario 2
A trigger is generated if a given sequence of 2 code events is executed.
Figure 6-28. Scenario 2a
SCR2=0101
SCR1=0011
State1
M1
M2
State2
Final State
A trigger is generated if a given sequence of 2 code events is executed, whereby the first event is entry into
a range (COMPA,COMPB configured for range mode). M1 is disabled in range modes.
Figure 6-29. Scenario 2b
SCR2=0101
SCR1=0111
State1
M01
M2
State2
Final State
A trigger is generated if a given sequence of 2 code events is executed, whereby the second event is entry
into a range (COMPA,COMPB configured for range mode)
Figure 6-30. Scenario 2c
SCR2=0011
SCR1=0010
State1
M2
State2
M0
Final State
All 3 scenarios 2a,2b,2c are possible with the S12SDBGV1 SCR encoding
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S12S Debug Module (S12SDBGV2)
6.5.4
Scenario 3
A trigger is generated immediately when one of up to 3 given events occurs
Figure 6-31. Scenario 3
SCR1=0000
State1
M012
Final State
Scenario 3 is possible with S12SDBGV1 SCR encoding
6.5.5
Scenario 4
Trigger if a sequence of 2 events is carried out in an incorrect order. Event A must be followed by event B
and event B must be followed by event A. 2 consecutive occurrences of event A without an intermediate
event B cause a trigger. Similarly 2 consecutive occurrences of event B without an intermediate event A
cause a trigger. This is possible by using CompA and CompC to match on the same address as shown.
Figure 6-32. Scenario 4a
SCR1=0100 State1
M1
SCR3=0001
State 3
M0
State2
M2
M0
M1
M1
SCR2=0011
Final State
This scenario is currently not possible using 2 comparators only. S12SDBGV2 makes it possible with 2
comparators, State 3 allowing a M0 to return to state 2, whilst a M2 leads to final state as shown.
Figure 6-33. Scenario 4b (with 2 comparators)
SCR1=0110 State1
M2
SCR3=1110
State 3
M0
State2
M0
M01
M2
M2
SCR2=1100
M1 disabled in
range mode
Final State
The advantage of using only 2 channels is that now range comparisons can be included (channel0)
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S12S Debug Module (S12SDBGV2)
This however violates the S12SDBGV1 specification, which states that a match leading to final state
always has priority in case of a simultaneous match, whilst priority is also given to the lowest channel
number. For S12SDBG the corresponding CPU priority decoder is removed to support this, such that on
simultaneous taghits, taghits pointing to final state have highest priority. If no taghit points to final state
then the lowest channel number has priority. Thus with the above encoding from State3, the CPU and DBG
would break on a simultaneous M0/M2.
6.5.6
Scenario 5
Trigger if following event A, event C precedes event B. i.e. the expected execution flow is A->B->C.
Figure 6-34. Scenario 5
SCR2=0110
SCR1=0011
State1
M1
State2
M0
Final State
M2
Scenario 5 is possible with the S12SDBGV1 SCR encoding
6.5.7
Scenario 6
Trigger if event A occurs twice in succession before any of 2 other events (BC) occurs. This scenario is
not possible using the S12SDBGV1 SCR encoding. S12SDBGV2 includes additions shown in red. The
change in SCR1 encoding also has the advantage that a State1->State3 transition using M0 is now possible.
This is advantageous because range and data bus comparisons use channel0 only.
Figure 6-35. Scenario 6
SCR3=1010
SCR1=1001
State1
M0
State3
M0
Final State
M12
6.5.8
Scenario 7
Trigger when a series of 3 events is executed out of order. Specifying the event order as M1,M2,M0 to run
in loops (120120120). Any deviation from that order should trigger. This scenario is not possible using the
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S12S Debug Module (S12SDBGV2)
S12SDBGV1 SCR encoding because OR possibilities are very limited in the channel encoding. By adding
OR forks as shown in red this scenario is possible.
Figure 6-36. Scenario 7
M01
SCR2=1100
SCR1=1101
State1
M1
SCR3=1101
M2
State2
State3
M12
Final State
M0
M02
On simultaneous matches the lowest channel number has priority so with this configuration the forking
from State1 has the peculiar effect that a simultaneous match0/match1 transitions to final state but a
simultaneous match2/match1transitions to state2.
6.5.9
Scenario 8
Trigger when a routine/event at M2 follows either M1 or M0.
Figure 6-37. Scenario 8a
SCR2=0101
SCR1=0111
State1
M01
M2
State2
Final State
Trigger when an event M2 is followed by either event M0 or event M1
Figure 6-38. Scenario 8b
SCR2=0111
SCR1=0010
State1
M2
State2
M01
Final State
Scenario 8a and 8b are possible with the S12SDBGV1 and S12SDBGV2 SCR encoding
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S12S Debug Module (S12SDBGV2)
6.5.10
Scenario 9
Trigger when a routine/event at A (M2) does not follow either B or C (M1 or M0) before they are executed
again. This cannot be realized with theS12SDBGV1 SCR encoding due to OR limitations. By changing
the SCR2 encoding as shown in red this scenario becomes possible.
Figure 6-39. Scenario 9
SCR2=1111
SCR1=0111
State1
M01
State2
M01
Final State
M2
6.5.11
Scenario 10
Trigger if an event M0 occurs following up to two successive M2 events without the resetting event M1.
As shown up to 2 consecutive M2 events are allowed, whereby a reset to State1 is possible after either one
or two M2 events. If an event M0 occurs following the second M2, before M1 resets to State1 then a trigger
is generated. Configuring CompA and CompC the same, it is possible to generate a breakpoint on the third
consecutive occurrence of event M0 without a reset M1.
Figure 6-40. Scenario 10a
M1
SCR1=0010
State1
M2
SCR2=0100
SCR3=0010
M2
State2
M0
State3
Final State
M1
Figure 6-41. Scenario 10b
M0
SCR2=0011
SCR1=0010
State1
M2
State2
SCR3=0000
M1
State3
Final State
M0
Scenario 10b shows the case that after M2 then M1 must occur before M0. Starting from a particular point
in code, event M2 must always be followed by M1 before M0. If after any M2, event M0 occurs before
M1 then a trigger is generated.
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Chapter 7
S12 Clock, Reset and Power Management Unit (S12CPMU)
Revision History
Version Revision Effective
Number
Date
Date
V01.00
16 Jan.07
16 Jan. 07
Author
Description of Changes
Initial release
V01.01
9 July 08
9 July 08
added IRCLK to Block Diagram
V01.02
7 Oct. 08
7 Oct. 08
clarified and detailed oscillator filter functionality
V01.03
11 Dec. 08 11 Dec. 08
added note, that startup time of external oscillator tUPOSC must be
considered, especially when entering Pseudo Stop Mode
V01.04
17 Jun. 09 17 Jun. 09
Modified reset phase descriptions to reference fVCORST instead of
fPLLRST and correct typo of RESET pin sample point from 64 to 256
cycles in section: Description of Reset Operation
V01.05
27 Apr. 10
Major rework fixing typos, figures and tables and improved
description of Adaptive Oscillator Filter.
7.1
27 Apr. 10
Introduction
This specification describes the function of the Clock, Reset and Power Management Unit (S12CPMU).
• The Pierce oscillator (OSCLCP) provides a robust, low-noise and low-power external clock source.
It is designed for optimal start-up margin with typical crystal oscillators.
• The Voltage regulator (IVREG) operates from the range 3.13V to 5.5V. It provides all the required
chip internal voltages and voltage monitors.
• The Phase Locked Loop (PLL) provides a highly accurate frequency multiplier with internal filter.
• The Internal Reference Clock (IRC1M) provides a1MHz clock.
7.1.1
Features
The Pierce Oscillator (OSCLCP) contains circuitry to dynamically control current gain in the output
amplitude. This ensures a signal with low harmonic distortion, low power and good noise immunity.
• Supports crystals or resonators from 4MHz to 16MHz.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
•
•
•
•
•
•
High noise immunity due to input hysteresis and spike filtering.
Low RF emissions with peak-to-peak swing limited dynamically
Transconductance (gm) sized for optimum start-up margin for typical crystals
Dynamic gain control eliminates the need for external current limiting resistor
Integrated resistor eliminates the need for external bias resistor.
Low power consumption: Operates from internal 1.8V (nominal) supply, Amplitude control limits
power
The Voltage Regulator (IVREG) has the following features:
• Input voltage range from 3.13V to 5.5V
• Low-voltage detect (LVD) with low-voltage interrupt (LVI)
• Power-on reset (POR)
• Low-voltage reset (LVR)
The Phase Locked Loop (PLL) has the following features:
• highly accurate and phase locked frequency multiplier
• Configurable internal filter for best stability and lock time.
• Frequency modulation for defined jitter and reduced emission
• Automatic frequency lock detector
• Interrupt request on entry or exit from locked condition
• Reference clock either external (crystal) or internal square wave (1MHz IRC1M) based.
• PLL stability is sufficient for LIN communication, even if using IRC1M as reference clock
The Internal Reference Clock (IRC1M) has the following features:
• Trimmable in frequency
• Factory trimmed value for 1MHz in Flash Memory, can be overwritten by application if required
Other features of the S12CPMU include
• Clock monitor to detect loss of crystal
• Autonomous periodical interrupt (API)
• Bus Clock Generator
— Clock switch to select either PLLCLK or external crystal/resonator based Bus Clock
— PLLCLK divider to adjust system speed
• System Reset generation from the following possible sources:
— Power-on reset (POR)
— Low-voltage reset (LVR)
— Illegal address access
— COP time out
— Loss of oscillation (clock monitor fail)
— External pin RESET
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.1.2
Modes of Operation
This subsection lists and briefly describes all operating modes supported by the S12CPMU.
7.1.2.1
Run Mode
The voltage regulator is in Full Performance Mode (FPM).
The Phase Locked Loop (PLL) is on.
The Internal Reference Clock (IRC1M) is on.
The API is available.
• PLL Engaged Internal (PEI)
— This is the default mode after System Reset and Power-On Reset.
— The Bus Clock is based on the PLLCLK.
— After reset the PLL is configured for 64MHz VCOCLK operation
Post divider is 0x03, so PLLCLK is VCOCLK divided by 4, that is 16MHz and Bus Clock is
8MHz.
The PLL can be re-configured for other bus frequencies.
— The reference clock for the PLL (REFCLK) is based on internal reference clock IRC1M
• PLL Engaged External (PEE)
— The Bus Clock is based on the PLLCLK.
— This mode can be entered from default mode PEI by performing the following steps:
– Configure the PLL for desired bus frequency.
– Program the reference divider (REFDIV[3:0] bits) to divide down oscillator frequency if
necessary.
– Enable the external oscillator (OSCE bit)
• PLL Bypassed External (PBE)
— The Bus Clock is based on the Oscillator Clock (OSCCLK).
— This mode can be entered from default mode PEI by performing the following steps:
– Enable the external oscillator (OSCE bit)
– Wait for oscillator to start up (UPOSC=1)
– Select the Oscillator Clock (OSCCLK) as Bus Clock (PLLSEL=0).
— The PLLCLK is still on to filter possible spikes of the external oscillator clock.
7.1.2.2
Wait Mode
For S12CPMU Wait Mode is the same as Run Mode.
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7.1.2.3
Stop Mode
This mode is entered by executing the CPU STOP instruction.
The voltage regulator is in Reduced Power Mode (RPM).
The API is available.
The Phase Locked Loop (PLL) is off.
The Internal Reference Clock (IRC1M) is off.
Core Clock, Bus Clock and BDM Clock are stopped.
Depending on the setting of the PSTP and the OSCE bit, Stop Mode can be differentiated between Full
Stop Mode (PSTP = 0 or OSCE=0) and Pseudo Stop Mode (PSTP = 1 and OSCE=1).
• Full Stop Mode (PSTP=0 or OSCE=0)
The external oscillator (OSCLCP) is disabled.
After wake-up from Full Stop Mode the Core Clock and Bus Clock are running on PLLCLK
(PLLSEL=1). After wake-up from Full Stop Mode COP and RTI are running on IRCCLK
(COPOSCSEL=0, RTIOSCSEL=0).
• Pseudo Stop Mode (PSTP=1 and OSCE=1)
The external oscillator (OSCLCP) continues torun. If the respective enable bits are set the COP and
RTI will continue to run.
The clock configuration bits PLLSEL, COPOSCSEL, RTIOSCSEL are unchanged.
NOTE
When starting up the external oscillator (either by programming OSCE bit
to 1 or on exit from Full Stop Mode with OSCE bit already 1) the software
must wait for a minimum time equivalent to the startup-time of the external
oscillator tUPOSC before entering Pseudo Stop Mode.
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7.1.3
S12CPMU Block Diagram
Illegal Address Access
MMC
VDDR
VDD, VDDPLL, VDDF
(core supplies)
Low Voltage Detect VDDA
VSSPLL
VSS
VDDX
VSSX
LVIE Low Voltage Interrupt
LVDS
Low Voltage Detect VDDX
Voltage
Regulator
3.13 to 5.5V
VDDA
VSSA
ILAF
LVRF
Power-On Detect
S12CPMU
PORF
RESET
UPOSC
Loop
EXTAL Controlled
Pierce
Oscillator
XTAL (OSCLCP)
4MHz-16MHz REFDIV[3:0]
OSCBW
Reference
Divider
Internal
Reference
Clock
(IRC1M)
oscillator status Interrupt
OSCIE
UPOSC=0 sets PLLSEL bit
adaptive
spike
filter
IRCTRIM[9:0]
Power-On Reset
System Reset
Reset
Generator
monitor fail
Clock
Monitor
PSTP
COP time out
&
OSCCLK
CAN_OSCCLK
(to MSCAN)
OSCFILT[4:0]
PLLSEL
POSTDIV[4:0]
ECLK2X
(Core Clock)
Post
Divider
1,2,..,32
divide
by 4
PLLCLK
ECLK
divide
by 2 (Bus Clock)
IRCCLK
(to LCD)
OSCE
VCOFRQ[1:0]
divide
by 8
VCOCLK
Lock
detect
REFCLK
FBCLK
Phase
locked
Loop with
internal
Filter (PLL)
HTDS
HTIE
HT Interrupt
High
Temperature
Sense
REFFRQ[1:0]
LOCK
LOCKIE
Divide by
2*(SYNDIV+1)
BDM Clock
Bus Clock
RC
Osc.
ACLK
PLL Lock Interrupt
Autonomous
API_EXTCLK
Periodic
Interrupt (API)
SYNDIV[5:0]
APICLK
UPOSC
UPOSC=0 clears
IRCCLK
COPCLK COP
OSCCLK
COPOSCSEL
Watchdog
PCE
COP time out
to Reset
Generator
CPMUCOP
IRCCLK
RTICLK
OSCCLK
RTIOSCSEL
APIE
API Interrupt
RTIE
RTI Interrupt
Real Time
Interrupt (RTI)
PRE
CPMURTI
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Figure 7-1. Block diagram of S12CPMU
Figure 7-2 shows a block diagram of the OSCLCP.
OSCCLK
Peak
Detector
Gain Control
VDDPLL = 1.8 V
VSSPLL
Rf
XTAL
EXTAL
Figure 7-2. OSCLCP Block Diagram
7.2
Signal Description
This section lists and describes the signals that connect off chip.
7.2.1
RESET
RESET is an active-low bidirectional pin. As an input it initializes the MCU asynchronously to a known
start-up state. As an open-drain output it indicates that an MCU-internal reset has been triggered.
7.2.2
EXTAL and XTAL
These pins provide the interface for a crystal to control the internal clock generator circuitry. EXTAL is
the external clock input or the input to the crystal oscillator amplifier. XTAL is the output of the crystal
oscillator amplifier. The MCU internal OSCCLK is derived from the EXTAL input frequency. If OSCE=0,
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Freescale Semiconductor
S12 Clock, Reset and Power Management Unit (S12CPMU)
the EXTAL pin is pulled down by an internal resistor of approximately 200 kΩ and the XTAL pin is pulled
down by an internal resistor of approximately 700 kΩ.
NOTE
Freescale recommends an evaluation of the application board and chosen
resonator or crystal by the resonator or crystal supplier.
Loop controlled circuit is not suited for overtone resonators and crystals.
7.2.3
TEMPSENSE — temperature sensor output voltage
Depending on the VSEL value either the voltage level generated by the temperature sensor or the VREG
bandgap voltage is driven to a special channel of the ATD Converter. See device level specification for
connectivity.
7.2.4
VDDR — Regulator Power Input Pin
VDDR is the power input of IVREG. All currents sourced into the regulator loads flow through this pin.
A chip external decoupling capacitor (100 nF...220 nF, X7R ceramic) between VDDR and VSS can
smooth ripple on VDDR.
7.2.5
VDDA, VSSA — Regulator Reference Supply Pins
VDDA/VSSA, which are relatively quiet, are used to supply the analog parts of the regulator. Internal
precision reference circuits are supplied from these signals. A chip external decoupling capacitor (100
nF...220 nF, X7R ceramic) between VDDA and VSSA can further improve the quality of this supply.
7.2.6
VSS, VSSPLL— Ground Pins
VSS and VSSPLL must be grounded.
7.2.7
VDDX, VSSX— Pad Supply Pins
This supply domain is monitored by the Low Voltage Reset circuit.
An off-chip decoupling capacitor (100 nF...220 nF, X7R ceramic) between VDDX and VSSX can further
improve the quality of this supply.
7.2.8
API_EXTCLK — API external clock output pin
This pin provides the signal selected via APIES and is enabled with APIEA bit. See device specification
to which pin it connects.
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203
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3
Memory Map and Registers
This section provides a detailed description of all registers accessible in the S12CPMU.
7.3.1
Module Memory Map
The S12CPMU registers are shown in Figure 7-3.
Addres
s
Name
0x0034
CPMU
SYNR
0x0035
CPMU
REFDIV
W
0x0036
CPMU
POSTDIV
W
0x0037
CPMUFLG
0x0038
CPMUINT
0x0039 CPMUCLKS
0x003A
CPMUPLL
0x003B
CPMURTI
0x003C CPMUCOP
Bit 7
R
W
R
R
R
W
R
W
R
W
R
6
W
R
W
4
VCOFRQ[1:0]
REFFRQ[1:0]
0
0
0
RTIF
PORF
LVRF
0
0
RTIE
PLLSEL
PSTP
0
0
RTDEC
RTR6
WCOP
RSBCK
3
2
1
Bit 0
SYNDIV[5:0]
0
W
R
5
0
REFDIV[3:0]
POSTDIV[4:0]
LOCKIF
LOCKIE
LOCK
ILAF
OSCIF
UPOSC
0
0
PRE
PCE
RTI
OSCSEL
COP
OSCSEL
0
0
0
0
RTR2
RTR1
RTR0
CR2
CR1
CR0
0
0
FM1
FM0
RTR5
RTR4
RTR3
0
0
0
WRTMASK
OSCIE
0
0x003D
RESERVED R
CPMUTEST0 W
0
0
0
0
0
0
0
0
0x003E
RESERVED R
CPMUTEST1 W
0
0
0
0
0
0
0
0
0x003F
CPMU
ARMCOP
R
0
0
0
0
0
0
0
0
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0x02F0
CPMU
HTCTL
R
0
0
W
HTIE
HTIF
0x02F1
CPMU
LVCTL
0
0
0
W
LVIE
LVIF
0x02F2
CPMU
APICTL
0
0
W
APIE
APIF
R
R
APICLK
VSEL
0
HTE
HTDS
0
0
LVDS
APIES
APIEA
APIFE
= Unimplemented or Reserved
Figure 7-3. CPMU Register Summary
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Freescale Semiconductor
S12 Clock, Reset and Power Management Unit (S12CPMU)
Addres
s
Name
0x02F3 CPMUAPITR
0x02F4 CPMUAPIRH
0x02F5 CPMUAPIRL
0x02F6
R
W
R
W
R
W
RESERVED R
CPMUTEST3 W
0x02F7 CPMUHTTR
R
W
CPMU
IRCTRIMH
W
0x02F9
CPMU
IRCTRIML
W
0x02FA
CPMUOSC
0x02FC
6
5
4
3
2
APITR5
APITR4
APITR3
APITR2
APITR1
APITR0
APIR15
APIR14
APIR13
APIR12
APIR11
APIR7
APIR6
APIR5
APIR4
0
0
0
0
0
0
0
HTOE
R
0x02F8
0x02FB CPMUPROT
Bit 7
TCTRIM[3:0]
R
R
W
R
1
Bit 0
0
0
APIR10
APIR9
APIR8
APIR3
APIR2
APIR1
APIR0
0
0
0
0
HTTR3
HTTR2
HTTR1
HTTR0
0
0
IRCTRIM[9:8]
IRCTRIM[7:0]
0
OSCE
OSCBW
OSCFILT[4:0]
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
RESERVED R
CPMUTEST2 W
PROT
0
= Unimplemented or Reserved
Figure 7-3. CPMU Register Summary
S12P-Family Reference Manual, Rev. 1.13
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205
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2
Register Descriptions
This section describes all the S12CPMU registers and their individual bits.
Address order is as listed in Figure 7-3.
7.3.2.1
S12CPMU Synthesizer Register (CPMUSYNR)
The CPMUSYNR register controls the multiplication factor of the PLL and selects the VCO frequency
range.
0x0034
7
6
5
4
3
2
1
0
1
1
1
R
VCOFRQ[1:0]
SYNDIV[5:0]
W
Reset
0
1
0
1
1
Figure 7-4. S12CPMU Synthesizer Register (CPMUSYNR)
Read: Anytime
Write: If PROT=0 (CPMUPROT register) and PLLSEL=1 (CPMUCLKS register), then write anytime.
Else write has no effect.
NOTE
Writing to this register clears the LOCK and UPOSC status bits.
If PLL has locked (LOCK=1)
f VCO = 2 × f REF × ( SYNDIV + 1 )
NOTE
fVCO must be within the specified VCO frequency lock range. Bus
frequency fbus must not exceed the specified maximum.
The VCOFRQ[1:0] bits are used to configure the VCO gain for optimal stability and lock time. For correct
PLL operation the VCOFRQ[1:0] bits have to be selected according to the actual target VCOCLK
frequency as shown in Table 7-1. Setting the VCOFRQ[1:0] bits incorrectly can result in a non functional
PLL (no locking and/or insufficient stability).
Table 7-1. VCO Clock Frequency Selection
VCOCLK Frequency Ranges
VCOFRQ[1:0]
32MHz <= fVCO<= 48MHz
00
48MHz < fVCO<= 64MHz
01
Reserved
10
Reserved
11
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.2
S12CPMU Reference Divider Register (CPMUREFDIV)
The CPMUREFDIV register provides a finer granularity for the PLL multiplier steps when using the
external oscillator as reference.
0x0035
7
6
R
5
4
0
0
3
2
REFFRQ[1:0]
1
0
1
1
REFDIV[3:0]
W
Reset
0
0
0
0
1
1
Figure 7-5. S12CPMU Reference Divider Register (CPMUREFDIV)
Read: Anytime
Write: If PROT=0 (CPMUPROT register) and PLLSEL=1 (CPMUCLKS register), then write anytime.
Else write has no effect.
NOTE
Write to this register clears the LOCK and UPOSC status bits.
If OSCLCP is enabled (OSCE=1)
f OSC
f REF = -----------------------------------( REFDIV + 1 )
If OSCLCP is disabled (OSCE=0)
f REF = f IRC1M
The REFFRQ[1:0] bits are used to configure the internal PLL filter for optimal stability and lock time. For
correct PLL operation the REFFRQ[1:0] bits have to be selected according to the actual REFCLK
frequency as shown in Table 7-2.
If IRC1M is selected as REFCLK (OSCE=0) the PLL filter is fixed configured for the 1MHz <= fREF <=
2MHz range. The bits can still be written but will have no effect on the PLL filter configuration.
For OSCE=1, setting the REFFRQ[1:0] bits incorrectly can result in a non functional PLL (no locking
and/or insufficient stability).
Table 7-2. Reference Clock Frequency Selection if OSC_LCP is enabled
REFCLK Frequency Ranges
(OSCE=1)
REFFRQ[1:0]
1MHz <= fREF <= 2MHz
00
2MHz < fREF <= 6MHz
01
6MHz < fREF <= 12MHz
10
fREF >12MHz
11
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207
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.3
S12CPMU Post Divider Register (CPMUPOSTDIV)
The POSTDIV register controls the frequency ratio between the VCOCLK and the PLLCLK.
0x0036
R
7
6
5
0
0
0
4
3
2
1
0
1
1
2
1
0
ILAF
OSCIF
Note 3
0
POSTDIV[4:0]
W
Reset
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 7-6. S12CPMU Post Divider Register (CPMUPOSTDIV)
Read: Anytime
Write: If PLLSEL=1 write anytime, else write has no effect.
If PLL is locked (LOCK=1)
f VCO
f PLL = ----------------------------------------( POSTDIV + 1 )
If PLL is not locked (LOCK=0)
f VCO
f PLL = --------------4
If PLL is selected (PLLSEL=1)
f PLL
f bus = ------------2
7.3.2.4
S12CPMU Flags Register (CPMUFLG)
This register provides S12CPMU status bits and flags.
0x0037
7
6
5
4
RTIF
PORF
LVRF
LOCKIF
0
Note 1
Note 2
0
R
3
LOCK
UPOSC
W
Reset
0
0
1. PORF is set to 1 when a power on reset occurs. Unaffected by System Reset.
2. LVRF is set to 1 when a low voltage reset occurs. Unaffected by System Reset. Set by power on reset.
3. ILAF is set to 1 when an illegal address reset occurs. Unaffected by System Reset. Cleared by power on reset.
= Unimplemented or Reserved
Figure 7-7. S12CPMU Flags Register (CPMUFLG)
Read: Anytime
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S12 Clock, Reset and Power Management Unit (S12CPMU)
Write: Refer to each bit for individual write conditions
Table 7-3. CPMUFLG Field Descriptions
Field
Description
7
RTIF
Real Time Interrupt Flag — RTIF is set to 1 at the end of the RTI period. This flag can only be cleared by writing
a 1. Writing a 0 has no effect. If enabled (RTIE=1), RTIF causes an interrupt request.
0 RTI time-out has not yet occurred.
1 RTI time-out has occurred.
6
PORF
Power on Reset Flag — PORF is set to 1 when a power on reset occurs. This flag can only be cleared by writing
a 1. Writing a 0 has no effect.
0 Power on reset has not occurred.
1 Power on reset has occurred.
5
LVRF
Low Voltage Reset Flag — LVRF is set to 1 when a low voltage reset occurs. This flag can only be cleared by
writing a 1. Writing a 0 has no effect.
0 Low voltage reset has not occurred.
1 Low voltage reset has occurred.
4
LOCKIF
PLL Lock Interrupt Flag — LOCKIF is set to 1 when LOCK status bit changes. This flag can only be cleared by
writing a 1. Writing a 0 has no effect.If enabled (LOCKIE=1), LOCKIF causes an interrupt request.
0 No change in LOCK bit.
1 LOCK bit has changed.
3
LOCK
Lock Status Bit — LOCK reflects the current state of PLL lock condition. Writes have no effect. While PLL is
unlocked (LOCK=0) fPLL is fVCO / 4 to protect the system from high core clock frequencies during the PLL
stabilization time tlock.
0 VCOCLK is not within the desired tolerance of the target frequency.
fPLL = fVCO/4.
1 VCOCLK is within the desired tolerance of the target frequency.
fPLL = fVCO/(POSTDIV+1).
2
ILAF
Illegal Address Reset Flag — ILAF is set to 1 when an illegal address reset occurs. Refer to MMC chapter for
details. This flag can only be cleared by writing a 1. Writing a 0 has no effect.
0 Illegal address reset has not occurred.
1 Illegal address reset has occurred.
1
OSCIF
Oscillator Interrupt Flag — OSCIF is set to 1 when UPOSC status bit changes. This flag can only be cleared
by writing a 1. Writing a 0 has no effect.If enabled (OSCIE=1), OSCIF causes an interrupt request.
0 No change in UPOSC bit.
1 UPOSC bit has changed.
0
UPOSC
Oscillator Status Bit — UPOSC reflects the status of the oscillator. Writes have no effect. While UPOSC=0 the
OSCCLK going to the MSCAN module is off. Entering Full Stop Mode UPOSC is cleared.
0 The oscillator is off or oscillation is not qualified by the PLL.
1 The oscillator is qualified by the PLL.
NOTE
The adaptive spike filter uses the VCO clock as a reference to continuously
qualify the external oscillator clock. Because of this, the PLL is always active
and a valid PLL configuration is required for the system to work properly.
Furthermore, the adaptive spike filter is used to determine the status of the
external oscillator (reflected in the UPOSC bit). Since this function also relies on
the VCO clock, loosing PLL lock status (LOCK=0, except for entering Pseudo
Stop Mode) means loosing the oscillator status information as well (UPOSC=0).
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.5
S12CPMU Interrupt Enable Register (CPMUINT)
This register enables S12CPMU interrupt requests.
0x0038
7
R
6
5
0
0
RTIE
4
3
2
0
0
LOCKIE
1
0
0
OSCIE
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 7-8. S12CPMU Interrupt Enable Register (CPMUINT)
Read: Anytime
Write: Anytime
Table 7-4. CRGINT Field Descriptions
Field
7
RTIE
Description
Real Time Interrupt Enable Bit
0 Interrupt requests from RTI are disabled.
1 Interrupt will be requested whenever RTIF is set.
4
LOCKIE
PLL Lock Interrupt Enable Bit
0 PLL LOCK interrupt requests are disabled.
1 Interrupt will be requested whenever LOCKIF is set.
1
OSCIE
Oscillator Corrupt Interrupt Enable Bit
0 Oscillator Corrupt interrupt requests are disabled.
1 Interrupt will be requested whenever OSCIF is set.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.6
S12CPMU Clock Select Register (CPMUCLKS)
This register controls S12CPMU clock selection.
0x0039
7
6
PLLSEL
PSTP
1
0
R
5
4
0
0
3
2
1
0
PRE
PCE
RTI
OSCSEL
COP
OSCSEL
0
0
0
0
W
Reset
0
0
= Unimplemented or Reserved
Figure 7-9. S12CPMU Clock Select Register (CPMUCLKS)
Read: Anytime
Write:
1.
2.
3.
4.
Only possible when PROT=0 (CPMUPROT register).
All bits anytime in Special Modes.
PLLSEL, PSTP, PRE, PCE, RTIOSCSEL: Anytime in Normal Mode.
COPOSCSEL: Anytime in normal mode until CPMUCOP write once has taken place.
If COPOSCSEL was cleared by UPOSC=0 (entering Full Stop Mode with COPOSCSEL=1
or insufficient OSCCLK quality), then COPOSCSEL can be set once again.
After writing CPMUCLKS register, it is strongly recommended to read
back CPMUCLKS register to make sure that write of PLLSEL,
RTIOSCSEL and COPOSCSEL was successful.
Table 7-5. CPMUCLKS Descriptions
Field
7
PLLSEL
6
PSTP
Description
PLL Select Bit
This bit selects the PLLCLK as source of the System Clocks (Core Clock and Bus Clock).
PLLSEL can only be set to 0, if UPOSC=1.
UPOSC= 0 sets the PLLSEL bit.
Entering Full Stop Mode sets the PLLSEL bit.
0 System clocks are derived from OSCCLK if oscillator is up (UPOSC=1, fbus = fosc / 2.
1 System clocks are derived from PLLCLK, fbus = fPLL / 2.
Pseudo Stop Bit
This bit controls the functionality of the oscillator during Stop Mode.
0 Oscillator is disabled in Stop Mode (Full Stop Mode).
1 Oscillator continues to run in Stop Mode (Pseudo Stop Mode), option to run RTI and COP.
Note: Pseudo Stop Mode allows for faster STOP recovery and reduces the mechanical stress and aging of the
resonator in case of frequent STOP conditions at the expense of a slightly increased power consumption.
Note: When starting up the external oscillator (either by programming OSCE bit to 1 or on exit from Full Stop
Mode with OSCE bit is already 1) the software must wait for a minimum time equivalent to the startup-time
of the external oscillator tUPOSC before entering Pseudo Stop Mode.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
Table 7-5. CPMUCLKS Descriptions (continued)
Field
Description
3
PRE
RTI Enable During Pseudo Stop Bit — PRE enables the RTI during Pseudo Stop Mode.
0 RTI stops running during Pseudo Stop Mode.
1 RTI continues running during Pseudo Stop Mode if RTIOSCSEL=1.
Note: If PRE=0 or RTIOSCSEL=0 then the RTI will go static while Stop Mode is active. The RTI counter will not
be reset.
2
PCE
COP Enable During Pseudo Stop Bit — PCE enables the COP during Pseudo Stop Mode.
0 COP stops running during Pseudo Stop Mode
1 COP continues running during Pseudo Stop Mode if COPOSCSEL=1
Note: If PCE=0 or COPOSCSEL=0 then the COP will go static while Stop Mode is active. The COP counter will
not be reset.
1
RTI Clock Select— RTIOSCSEL selects the clock source to the RTI. Either IRCCLK or OSCCLK. Changing the
RTIOSCSEL RTIOSCSEL bit re-starts the RTI time-out period.
RTIOSCSEL can only be set to 1, if UPOSC=1.
UPOSC= 0 clears the RTIOSCSEL bit.
0 RTI clock source is IRCCLK.
1 RTI clock source is OSCCLK.
0
COP Clock Select— COPOSCSEL selects the clock source to the COP. Either IRCCLK or OSCCLK. Changing
COPOSCSE the COPOSCSEL bit re-starts the COP time-out period.
L
COPOSCSEL can only be set to 1, if UPOSC=1.
UPOSC= 0 clears the COPOSCSEL bit.
0 COP clock source is IRCCLK.
1 COP clock source is OSCCLK
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Freescale Semiconductor
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.7
S12CPMU PLL Control Register (CPMUPLL)
This register controls the PLL functionality.
0x003A
R
7
6
0
0
5
4
FM1
FM0
0
0
3
2
1
0
0
0
0
0
0
0
0
0
W
Reset
0
0
Figure 7-10. S12CPMU PLL Control Register (CPMUPLL)
Read: Anytime
Write: Anytime if PROT=0 (CPMUPROT register) and PLLSEL=1 (CPMUCLKS register). Else write has
no effect.
NOTE
Write to this register clears the LOCK and UPOSC status bits.
NOTE
Care should be taken to ensure that the bus frequency does not exceed the
specified maximum when frequency modulation is enabled.
NOTE
The frequency modulation (FM1 and FM0) can not be used if the Oscillator
Filter is enabled.
Table 7-6. CPMUPLL Field Descriptions
Field
Description
5, 4
FM1, FM0
PLL Frequency Modulation Enable Bits — FM1 and FM0 enable frequency modulation on the VCOCLK. This
is to reduce noise emission. The modulation frequency is fref divided by 16. See Table 7-7 for coding.
Table 7-7. FM Amplitude selection
FM1
FM0
FM Amplitude /
fVCO Variation
0
0
FM off
0
1
±1%
1
0
±2%
1
1
±4%
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.8
S12CPMU RTI Control Register (CPMURTI)
This register selects the time-out period for the Real Time Interrupt.
The clock source for the RTI is either IRCCLK or OSCCLK depending on the setting of the RTIOSCSEL
bit. In Stop Mode with PSTP=1 (Pseudo Stop Mode) and RTIOSCSEL=1 the RTI continues to run, else
the RTI counter halts in Stop Mode.
0x003B
7
6
5
4
3
2
1
0
RTDEC
RTR6
RTR5
RTR4
RTR3
RTR2
RTR1
RTR0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 7-11. S12CPMU RTI Control Register (CPMURTI)
Read: Anytime
Write: Anytime
NOTE
A write to this register starts the RTI time-out period. A change of the
RTIOSCSEL bit (writing a different value or loosing UPOSC status)
re-starts the RTI time-out period.
Table 7-8. CPMURTI Field Descriptions
Field
Description
7
RTDEC
Decimal or Binary Divider Select Bit — RTDEC selects decimal or binary based prescaler values.
0 Binary based divider value. See Table 7-9
1 Decimal based divider value. See Table 7-10
6–4
RTR[6:4]
Real Time Interrupt Prescale Rate Select Bits — These bits select the prescale rate for the RTI. See Table 7-9
and Table 7-10.
3–0
RTR[3:0]
Real Time Interrupt Modulus Counter Select Bits — These bits select the modulus counter target value to
provide additional granularity.Table 7-9 and Table 7-10 show all possible divide values selectable by the
CPMURTI register.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
Table 7-9. RTI Frequency Divide Rates for RTDEC = 0
RTR[6:4] =
RTR[3:0]
1
000
(OFF)
001
(210)
010
(211)
011
(212)
100
(213)
101
(214)
110
(215)
111
(216)
0000 (÷1)
OFF1
210
211
212
213
214
215
216
0001 (÷2)
OFF
2x210
2x211
2x212
2x213
2x214
2x215
2x216
0010 (÷3)
OFF
3x210
3x211
3x212
3x213
3x214
3x215
3x216
0011 (÷4)
OFF
4x210
4x211
4x212
4x213
4x214
4x215
4x216
0100 (÷5)
OFF
5x210
5x211
5x212
5x213
5x214
5x215
5x216
0101 (÷6)
OFF
6x210
6x211
6x212
6x213
6x214
6x215
6x216
0110 (÷7)
OFF
7x210
7x211
7x212
7x213
7x214
7x215
7x216
0111 (÷8)
OFF
8x210
8x211
8x212
8x213
8x214
8x215
8x216
1000 (÷9)
OFF
9x210
9x211
9x212
9x213
9x214
9x215
9x216
1001 (÷10)
OFF
10x210
10x211
10x212
10x213
10x214
10x215
10x216
1010 (÷11)
OFF
11x210
11x211
11x212
11x213
11x214
11x215
11x216
1011 (÷12)
OFF
12x210
12x211
12x212
12x213
12x214
12x215
12x216
1100 (÷13)
OFF
13x210
13x211
13x212
13x213
13x214
13x215
13x216
1101 (÷14)
OFF
14x210
14x211
14x212
14x213
14x214
14x215
14x216
1110 (÷15)
OFF
15x210
15x211
15x212
15x213
15x214
15x215
15x216
1111 (÷16)
OFF
16x210
16x211
16x212
16x213
16x214
16x215
16x216
Denotes the default value out of reset.This value should be used to disable the RTI to ensure future backwards compatibility.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
Table 7-10. RTI Frequency Divide Rates for RTDEC=1
RTR[6:4] =
RTR[3:0]
000
(1x103)
001
(2x103)
010
(5x103)
011
(10x103)
100
(20x103)
101
(50x103)
110
(100x103)
111
(200x103)
0000 (÷1)
1x103
2x103
5x103
10x103
20x103
50x103
100x103
200x103
0001 (÷2)
2x103
4x103
10x103
20x103
40x103
100x103
200x103
400x103
0010 (÷3)
3x103
6x103
15x103
30x103
60x103
150x103
300x103
600x103
0011 (÷4)
4x103
8x103
20x103
40x103
80x103
200x103
400x103
800x103
0100 (÷5)
5x103
10x103
25x103
50x103
100x103
250x103
500x103
1x106
0101 (÷6)
6x103
12x103
30x103
60x103
120x103
300x103
600x103
1.2x106
0110 (÷7)
7x103
14x103
35x103
70x103
140x103
350x103
700x103
1.4x106
0111 (÷8)
8x103
16x103
40x103
80x103
160x103
400x103
800x103
1.6x106
1000 (÷9)
9x103
18x103
45x103
90x103
180x103
450x103
900x103
1.8x106
1001 (÷10)
10 x103
20x103
50x103
100x103
200x103
500x103
1x106
2x106
1010 (÷11)
11 x103
22x103
55x103
110x103
220x103
550x103
1.1x106
2.2x106
1011 (÷12)
12x103
24x103
60x103
120x103
240x103
600x103
1.2x106
2.4x106
1100 (÷13)
13x103
26x103
65x103
130x103
260x103
650x103
1.3x106
2.6x106
1101 (÷14)
14x103
28x103
70x103
140x103
280x103
700x103
1.4x106
2.8x106
1110 (÷15)
15x103
30x103
75x103
150x103
300x103
750x103
1.5x106
3x106
1111 (÷16)
16x103
32x103
80x103
160x103
320x103
800x103
1.6x106
3.2x106
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.9
S12CPMU COP Control Register (CPMUCOP)
This register controls the COP (Computer Operating Properly) watchdog.
The clock source for the COP is either IRCCLK or OSCCLK depending on the setting of the
COPOSCSEL bit. In Stop Mode with PSTP=1 (Pseudo Stop Mode), COPOSCSEL=1 and PCE=1 the COP
continues to run, else the COP counter halts in Stop Mode.
0x003C
7
6
WCOP
RSBCK
R
W
Reset
5
4
3
0
0
0
2
1
0
CR2
CR1
CR0
F
F
F
WRTMASK
F
0
0
0
0
After de-assert of System Reset the values are automatically loaded from the Flash memory. See Device specification for
details.
= Unimplemented or Reserved
Figure 7-12. S12CPMU COP Control Register (CPMUCOP)
Read: Anytime
Write:
1. RSBCK: anytime in special mode; write to “1” but not to “0” in normal mode
2. WCOP, CR2, CR1, CR0:
— Anytime in special mode, when WRTMASK is 0, otherwise it has no effect
— Write once in normal mode, when WRTMASK is 0, otherwise it has no effect.
– Writing CR[2:0] to “000” has no effect, but counts for the “write once” condition.
– Writing WCOP to “0” has no effect, but counts for the “write once” condition.
When a non-zero value is loaded from Flash to CR[2:0] the COP time-out period is started.
A change of the COPOSCSEL bit (writing a different value or loosing UPOSC status) re-starts the COP
time-out period.
In normal mode the COP time-out period is restarted if either of these conditions is true:
1. Writing a non-zero value to CR[2:0] (anytime in special mode, once in normal mode) with
WRTMASK = 0.
2. Writing WCOP bit (anytime in special mode, once in normal mode) with WRTMASK = 0.
3. Changing RSBCK bit from “0” to “1”.
In special mode, any write access to CPMUCOP register restarts the COP time-out period.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
Table 7-11. CPMUCOP Field Descriptions
Field
Description
7
WCOP
Window COP Mode Bit — When set, a write to the CPMUARMCOP register must occur in the last 25% of the
selected period. A write during the first 75% of the selected period generates a COP reset. As long as all writes
occur during this window, $55 can be written as often as desired. Once $AA is written after the $55, the time-out
logic restarts and the user must wait until the next window before writing to CPMUARMCOP. Table 7-12 shows
the duration of this window for the seven available COP rates.
0 Normal COP operation
1 Window COP operation
6
RSBCK
COP and RTI Stop in Active BDM Mode Bit
0 Allows the COP and RTI to keep running in Active BDM mode.
1 Stops the COP and RTI counters whenever the part is in Active BDM mode.
5
Write Mask for WCOP and CR[2:0] Bit — This write-only bit serves as a mask for the WCOP and CR[2:0] bits
WRTMASK while writing the CPMUCOP register. It is intended for BDM writing the RSBCK without changing the content of
WCOP and CR[2:0].
0 Write of WCOP and CR[2:0] has an effect with this write of CPMUCOP
1 Write of WCOP and CR[2:0] has no effect with this write of CPMUCOP.
(Does not count for “write once”.)
2–0
CR[2:0]
COP Watchdog Timer Rate Select — These bits select the COP time-out rate (see Table 7-12). Writing a
nonzero value to CR[2:0] enables the COP counter and starts the time-out period. A COP counter time-out
causes a System Reset. This can be avoided by periodically (before time-out) initializing the COP counter via
the CPMUARMCOP register.
While all of the following four conditions are true the CR[2:0], WCOP bits are ignored and the COP operates at
highest time-out period (2 24 cycles) in normal COP mode (Window COP mode disabled):
1) COP is enabled (CR[2:0] is not 000)
2) BDM mode active
3) RSBCK = 0
4) Operation in special mode
Table 7-12. COP Watchdog Rates
CR2
CR1
CR0
COPCLK
Cycles to time-out
(COPCLK is either IRCCLK or
OSCCLK depending on the
COPOSCSEL bit)
0
0
0
COP disabled
0
0
1
2 14
0
1
0
2 16
0
1
1
2 18
1
0
0
2 20
1
0
1
2 22
1
1
0
2 23
1
1
1
2 24
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.10
Reserved Register CPMUTEST0
NOTE
This reserved register is designed for factory test purposes only, and is not
intended for general user access. Writing to this register when in special
mode can alter the S12CPMU’s functionality.
0x003D
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 7-13. Reserved Register (CPMUTEST0)
Read: Anytime
Write: Only in special mode
7.3.2.11
Reserved Register CPMUTEST1
NOTE
This reserved register is designed for factory test purposes only, and is not
intended for general user access. Writing to this register when in special
mode can alter the S12CPMU’s functionality.
0x003E
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 7-14. Reserved Register (CPMUTEST1)
Read: Anytime
Write: Only in special mode
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219
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.12
S12CPMU COP Timer Arm/Reset Register (CPMUARMCOP)
This register is used to restart the COP time-out period.
0x003F
7
6
5
4
3
2
1
0
R
0
0
0
0
0
0
0
0
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
Reset
Figure 7-15. S12CPMU CPMUARMCOP Register
Read: Always reads $00
Write: Anytime
When the COP is disabled (CR[2:0] = “000”) writing to this register has no effect.
When the COP is enabled by setting CR[2:0] nonzero, the following applies:
Writing any value other than $55 or $AA causes a COP reset. To restart the COP time-out period
write $55 followed by a write of $AA. These writes do not need to occur back-to-back, but the
sequence ($55, $AA) must be completed prior to COP end of time-out period to avoid a COP reset.
Sequences of $55 writes are allowed. When the WCOP bit is set, $55 and $AA writes must be done
in the last 25% of the selected time-out period; writing any value in the first 75% of the selected
period will cause a COP reset.
7.3.2.13
High Temperature Control Register (CPMUHTCTL)
The CPMUHTCTL register configures the temperature sense features.
0x02F0
R
7
6
0
0
0
0
W
Reset
5
VSEL
0
4
0
0
3
HTE
0
2
HTDS
0
1
0
HTIE
HTIF
0
0
= Unimplemented or Reserved
Read: Anytime
Write: VSEL, HTE, HTIE and HTIF are write anytime, HTDS is read only
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S12 Clock, Reset and Power Management Unit (S12CPMU)
Figure 7-16. Voltage Access Select
VBG
Ref
VSEL
TEMPSENSE
ATD
Channel
C
HTD
Table 7-13. CPMUHTCTL Field Descriptions
Field
Description
5
VSEL
Voltage Access Select Bit — If set, the bandgap reference voltage VBG can be accessed internally (i.e.
multiplexed to an internal Analog to Digital Converter channel). If not set, the die temperature proportional
voltage VHT of the temperature sense can be accessed internally. See device level specification for connectivity.
0 An internal temperature proportional voltage VHT can be accessed internally.
1 Bandgap reference voltage VBG can be accessed internally.
3
HTE
High Temperature Enable Bit — This bit enables the high temperature sensor.
0 The temperature sense is disabled.
1 The temperature sense is enabled.
2
HTDS
High Temperature Detect Status Bit — This read-only status bit reflects the temperature. status. Writes have
no effect.
0 Junction Temperature is below level THTID or RPM.
1 Junction Temperature is above level THTIA and FPM.
1
HTIE
High Temperature Interrupt Enable Bit
0 Interrupt request is disabled.
1 Interrupt will be requested whenever HTIF is set.
0
HTIF
High Temperature Interrupt Flag — HTIF — High Temperature Interrupt Flag
HTIF is set to 1 when HTDS status bit changes. This flag can only be cleared by writing a 1.
Writing a 0 has no effect. If enabled (HTIE=1), HTIF causes an interrupt request.
0 No change in HTDS bit.
1 HTDS bit has changed.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.14
Low Voltage Control Register (CPMULVCTL)
The CPMULVCTL register allows the configuration of the low-voltage detect features.
0x02F1
R
7
6
5
4
3
2
0
0
0
0
0
LVDS
0
0
0
0
0
U
W
Reset
1
0
LVIE
LVIF
0
U
The Reset state of LVDS and LVIF depends on the external supplied VDDA level
= Unimplemented or Reserved
Figure 7-17. Low Voltage Control Register (CPMULVCTL)
Read: Anytime
Write: LVIE and LVIF are write anytime, LVDS is read only
Table 7-14. CPMULVCTL Field Descriptions
Field
Description
2
LVDS
Low-Voltage Detect Status Bit — This read-only status bit reflects the voltage level on VDDA. Writes have no
effect.
0 Input voltage VDDA is above level VLVID or RPM.
1 Input voltage VDDA is below level VLVIA and FPM.
1
LVIE
Low-Voltage Interrupt Enable Bit
0 Interrupt request is disabled.
1 Interrupt will be requested whenever LVIF is set.
0
LVIF
Low-Voltage Interrupt Flag — LVIF is set to 1 when LVDS status bit changes. This flag can only be cleared by
writing a 1. Writing a 0 has no effect. If enabled (LVIE = 1), LVIF causes an interrupt request.
0 No change in LVDS bit.
1 LVDS bit has changed.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.15
Autonomous Periodical Interrupt Control Register (CPMUAPICTL)
The CPMUAPICTL register allows the configuration of the autonomous periodical interrupt features.
0x02F2
7
R
W
Reset
APICLK
0
6
5
0
0
0
0
4
3
2
1
0
APIES
APIEA
APIFE
APIE
APIF
0
0
0
0
0
= Unimplemented or Reserved
Figure 7-18. Autonomous Periodical Interrupt Control Register (CPMUAPICTL)
Read: Anytime
Write: Anytime
Table 7-15. CPMUAPICTL Field Descriptions
Field
7
APICLK
Description
Autonomous Periodical Interrupt Clock Select Bit — Selects the clock source for the API. Writable only if
APIFE = 0. APICLK cannot be changed if APIFE is set by the same write operation.
0 Autonomous periodical interrupt clock used as source.
1 Bus Clock used as source.
4
APIES
Autonomous Periodical Interrupt External Select Bit — Selects the waveform at the external pin
API_EXTCLK as shown in Figure 7-19. See device level specification for connectivity of API_EXTCLK pin.
0 If APIEA and APIFE are set, at the external pin API_EXTCLK periodic high pulses are visible at the end of
every selected period with the size of half of the min period (APIR=0x0000 in Table 7-19).
1 If APIEA and APIFE are set, at the external pin API_EXTCLK a clock is visible with 2 times the selected API
Period.
3
APIEA
Autonomous Periodical Interrupt External Access Enable Bit — If set, the waveform selected by bit APIES
can be accessed externally. See device level specification for connectivity.
0 Waveform selected by APIES can not be accessed externally.
1 Waveform selected by APIES can be accessed externally, if APIFE is set.
2
APIFE
Autonomous Periodical Interrupt Feature Enable Bit — Enables the API feature and starts the API timer
when set.
0 Autonomous periodical interrupt is disabled.
1 Autonomous periodical interrupt is enabled and timer starts running.
1
APIE
Autonomous Periodical Interrupt Enable Bit
0 API interrupt request is disabled.
1 API interrupt will be requested whenever APIF is set.
0
APIF
Autonomous Periodical Interrupt Flag — APIF is set to 1 when the in the API configured time has elapsed.
This flag can only be cleared by writing a 1. Writing a 0 has no effect. If enabled (APIE = 1), APIF causes an
interrupt request.
0 API time-out has not yet occurred.
1 API time-out has occurred.
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223
S12 Clock, Reset and Power Management Unit (S12CPMU)
Figure 7-19. Waveform selected on API_EXTCLK pin (APIEA=1, APIFE=1)
API min period / 2
APIES=0
API period
APIES=1
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.16
Autonomous Periodical Interrupt Trimming Register (CPMUAPITR)
The CPMUAPITR register configures the trimming of the API time-out period.
0x02F3
7
R
W
Reset
6
5
4
3
2
APITR5
APITR4
APITR3
APITR2
APITR1
APITR0
F
F
F
F
F
F
1
0
0
0
0
0
After de-assert of System Reset a value is automatically loaded from the Flash memory.
Figure 7-20. Autonomous Periodical Interrupt Trimming Register (CPMUAPITR)
Read: Anytime
Write: Anytime
Table 7-16. CPMUAPITR Field Descriptions
Field
7–2
APITR[5:0]
Description
Autonomous Periodical Interrupt Period Trimming Bits — See Table 7-17 for trimming effects. The
APITR[5:0] value represents a signed number influencing the ACLK period time.
Table 7-17. Trimming Effect of APITR
Bit
Trimming Effect
APITR[5]
Increases period
APITR[4]
Decreases period less than APITR[5] increased it
APITR[3]
Decreases period less than APITR[4]
APITR[2]
Decreases period less than APITR[3]
APITR[1]
Decreases period less than APITR[2]
APITR[0]
Decreases period less than APITR[1]
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225
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.17
Autonomous Periodical Interrupt Rate High and Low Register
(CPMUAPIRH / CPMUAPIRL)
The CPMUAPIRH and CPMUAPIRL registers allow the configuration of the autonomous periodical
interrupt rate.
0x02F4
R
W
Reset
7
6
5
4
3
2
1
0
APIR15
APIR14
APIR13
APIR12
APIR11
APIR10
APIR9
APIR8
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 7-21. Autonomous Periodical Interrupt Rate High Register (CPMUAPIRH)
0x02F5
R
W
Reset
7
6
5
4
3
2
1
0
APIR7
APIR6
APIR5
APIR4
APIR3
APIR2
APIR1
APIR0
0
0
0
0
0
0
0
0
Figure 7-22. Autonomous Periodical Interrupt Rate Low Register (CPMUAPIRL)
Read: Anytime
Write: If APIFE=0, then write anytime, else writes have no effect.
Table 7-18. CPMUAPIRH / CPMUAPIRL Field Descriptions
Field
15-0
APIR[15:0]
Description
Autonomous Periodical Interrupt Rate Bits — These bits define the time-out period of the API. See
Table 7-19 for details of the effect of the autonomous periodical interrupt rate bits.
The period can be calculated as follows depending on logical value of the APICLK bit:
APICLK=0: Period = 2*(APIR[15:0] + 1) * fACLK
APICLK=1: Period = 2*(APIR[15:0] + 1) * Bus Clock period
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S12 Clock, Reset and Power Management Unit (S12CPMU)
Table 7-19. Selectable Autonomous Periodical Interrupt Periods
1
APICLK
APIR[15:0]
Selected Period
0
0000
0.2 ms1
0
0001
0.4 ms1
0
0002
0.6 ms1
0
0003
0.8 ms1
0
0004
1.0 ms1
0
0005
1.2 ms1
0
.....
0
FFFD
13106.8 ms1
0
FFFE
13107.0 ms1
0
FFFF
13107.2 ms1
1
0000
2 * Bus Clock period
1
0001
4 * Bus Clock period
1
0002
6 * Bus Clock period
1
0003
8 * Bus Clock period
1
0004
10 * Bus Clock period
1
0005
12 * Bus Clock period
1
.....
.....
1
FFFD
131068 * Bus Clock period
1
FFFE
131070 * Bus Clock period
1
FFFF
131072 * Bus Clock period
.....
When fACLK is trimmed to 10KHz.
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227
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.18
Reserved Register CPMUTEST3
NOTE
This reserved register is designed for factory test purposes only, and is not
intended for general user access. Writing to this register when in special
mode can alter the S12CPMU’s functionality.
0x02F6
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 7-23. Reserved Register (CPMUTEST3)
Read: Anytime
Write: Only in special mode
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.19
High Temperature Trimming Register (CPMUHTTR)
The CPMUHTTR register configures the trimming of the S12CPMU temperature sense.
0x02F7
7
R
W
Reset
HTOE
0
6
5
4
0
0
0
0
0
0
3
2
1
0
HTTR3
HTTR2
HTTR1
HTTR0
F
F
F
F
After de-assert of System Reset a trim value is automatically loaded from the Flash memory. See Device specification for
details.
= Unimplemented or Reserved
Read: Anytime
Write: Anytime
Field
7
HTOE
3–0
HTTR[3:0]
Description
High Temperature Offset Enable Bit — If set the temperature sense offset is enabled.
0 The temperature sense offset is disabled. HTTR[3:0] bits don’t care.
1 The temperature sense offset is enabled. HTTR[3:0] select the temperature offset.
High Temperature Trimming Bits — See Table 1-27 for trimming effects.
Bit
Trimming Effect
HTTR[3]
Increases VHT twice of HTTR[2]
HTTR[2]
Increases VHT twice of HTTR[1]
HTTR[1]
Increases VHT twice of HTTR[0]
HTTR[0]
Increases VHT (to compensate Temperature Offset)
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.20
S12CPMU IRC1M Trim Registers (CPMUIRCTRIMH / CPMUIRCTRIML)
0x02F8
15
14
13
12
R
11
10
0
0
9
TCTRIM[3:0]
8
IRCTRIM[9:8]
W
Reset
F
F
F
F
0
0
F
F
After de-assert of System Reset a factory programmed trim value is automatically loaded from the Flash memory to
provide trimmed Internal Reference Frequency fIRC1M_TRIM.
Figure 7-24. S12CPMU IRC1M Trim High Register (CPMUIRCTRIMH)
0x02F9
7
6
5
4
3
2
1
0
F
F
F
R
IRCTRIM[7:0]
W
Reset
F
F
F
F
F
After de-assert of System Reset a factory programmed trim value is automatically loaded from the Flash memory to
provide trimmed Internal Reference Frequency fIRC1M_TRIM.
Figure 7-25. S12CPMU IRC1M Trim Low Register (CPMUIRCTRIML)
Read: Anytime
Write: If PROT=0 (CPMUPROT register), then write anytime. Else write has no effect
NOTE
Writes to these registers while PLLSEL=1 clears the LOCK and UPOSC
status bits.
Table 7-20. CPMUIRCTRIMH/L Field Descriptions
Field
Description
15-12
IRC1M temperature coefficient Trim Bits
TCTRIM[3:0] Trim bits for the Temperature Coefficient (TC) of the IRC1M frequency.
Table 7-21 shows the influence of the bits TCTRIM3:0] on the relationship between frequency and temperature.
Figure 7-27 shows an approximate TC variation, relative to the nominal TC of the IRC1M (i.e. for
TCTRIM[3:0]=0000 or 1000).
9-0
IRC1M Frequency Trim Bits — Trim bits for Internal Reference Clock
IRCTRIM[9:0] After System Reset the factory programmed trim value is automatically loaded into these registers, resulting in a
Internal Reference Frequency fIRC1M_TRIM. See device electrical characteristics for value of fIRC1M_TRIM.
The frequency trimming consists of two different trimming methods:
A rough trimming controlled by bits IRCTRIM[9:6] can be done with frequency leaps of about 6% in average.
A fine trimming controlled by the bits IRCTRIM[5:0] can be doe with frequency leaps of about 0.3% (this trimming
determines the precision of the frequency setting of 0.15%, i.e. 0.3% is the distance between two trimming
values).
Figure 7-26 shows the relationship between the trim bits and the resulting IRC1M frequency.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
IRC1M frequency (IRCCLK)
IRCTRIM[9:6]
{
1.5MHz
IRCTRIM[5:0]
......
1MHz
600KHz
IRCTRIM[9:0]
$000
$3FF
Figure 7-26. IRC1M Frequency Trimming Diagram
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231
S12 Clock, Reset and Power Management Unit (S12CPMU)
frequency
111
x1
]=0
[3:0
RIM
T
TC
0x1111
0x1110
0x1101
0x1100
0x1011
0x1010
0x1001
TC increases
0x0001
0x0010
0x0011
0x0100
0x0101
0x0110
0x0111
TC decreases
TCTRIM[3:0]=0x1000 or 0x0000 (nominal TC)
TCT
RIM
- 40C
[3:0
]=0x
011
1
150C
temperature
Figure 7-27. Influence of TCTRIM[3:0] on the Temperature Coefficient
NOTE
The frequency is not necessarily linear with the temperature (in most cases
it will not be). The above diagram is meant only to give the direction
(positive or negative) of the variation of the TC, relative to the nominal TC.
Setting TCTRIM[3:0] to 0x0000 or 0x1000 does not mean that the
temperature coefficient will be zero. These two combinations basically
switch off the TC compensation module, which results in the nominal TC of
the IRC1M.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
TCTRIM[3:0]
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
IRC1M indicative
relative TC variation
0 (nominal TC of the IRC1M)
-0.54%
-1.08%
-1.63%
-2.20%
-2.77%
-3.33%
-3.91%
0 (nominal TC of the IRC1M)
+0.54%
+1.07%
+1.59%
+2.11%
+2.62%
+3.12%
+3.62%
IRC1M indicative frequency drift for
relative TC variation
0%
-0.8%
-1.6%
-2.4%
-3.2%
-4.0%
-4.8%
-5.5%
0%
+0.8%
+1.6%
+2.4%
+3.2%
+4.0%
+4.8%
+5.5%
Table 7-21. TC trimming of the IRC1M frequency at ambient temperature
NOTE
Since the IRC1M frequency is not a linear function of the temperature, but
more like a parabola, the above relative TC variation is only an indication
and should be considered with care.
Be aware that the output frequency vary with TC trimming, A frequency
trimming correction is therefore necessary. The values provided in
Table 7-21 are typical values at ambient temperature which can vary from
device to device.
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233
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.21
S12CPMU Oscillator Register (CPMUOSC)
This registers configures the external oscillator (OSCLCP).
0x02FA
7
6
OSCE
OSCBW
0
0
R
5
4
3
2
1
0
0
0
0
OSCFILT[4:0]
W
Reset
0
0
0
0
Figure 7-28. S12CPMU Oscillator Register (CPMUOSC)
Read: Anytime
Write: If PROT=0 (CPMUPROT register) and PLLSEL=1 (CPMUCLKS register), then write anytime.
Else write has no effect.
NOTE.
Write to this register clears the LOCK and UPOSC status bits.
NOTE.
If the chosen VCOCLK-to-OSCCLK ratio divided by two is not an integer
number, then the filter can not be used and the OSCFILT[4:0] bits must be
set to 0.
Table 7-22. CPMUOSC Field Descriptions
Field
Description
7
OSCE
Oscillator Enable Bit — This bit enables the external oscillator (OSCLCP). The UPOSC status bit in the
CPMUFLG register indicates when the oscillation is stable and OSCCLK can be selected as Bus Clock or source
of the COP or RTI. A loss of oscillation will lead to a clock monitor reset.
0 External oscillator is disabled.
REFCLK for PLL is IRCCLK.
1 External oscillator is enabled.Clock monitor is enabled.
REFCLK for PLL is the external oscillator clock divided by REFDIV.
Note: When starting up the external oscillator (either by programming OSCE bit to 1 or on exit from Full Stop
Mode with OSCE bit is already 1) the software must wait for a minimum time equivalent to the startup-time
of the external oscillator tUPOSC before entering Pseudo Stop Mode.
6
OSCBW
Oscillator Filter Bandwidth Bit — If the VCOCLK frequency exceeds 25 MHz wide bandwidth must be
selected.The Oscillator Filter is described in more detail at Section 7.4.5.2, “The Adaptive Oscillator Filter.
0 Oscillator filter bandwidth is narrow (window for expected OSCCLK edge is one VCOCLK cycle).
1 Oscillator filter bandwidth is wide (window for expected OSCCLK edge is three VCOCLK cycles).
4-0
OSCFILT
Oscillator Filter Bits — When using the oscillator a noise filter can be enabled, which filters noise from the
OSCCLK and detects if the OSCCLK is qualified or not (quality status shown by bit UPOSC).
The fVCO -to- f OSC ratio divided by two must be an integer value. The OSCFILT[4:0] bits must be set to the
calculated integer value to enable the oscillator filter).
0x0000 Oscillator Filter disabled.
else Oscillator Filter enabled:
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Freescale Semiconductor
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.22
S12CPMU Protection Register (CPMUPROT)
This register protects the clock configuration registers from accidental overwrite:
CPMUSYNR, CPMUREFDIV, CPMUCLKS, CPMUPLL, CPMUIRCTRIMH/L and CPMUOSC
0x02FB
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
PROT
W
Reset
0
0
0
0
0
0
0
0
Figure 7-29. S12CPMU Protection Register (CPMUPROT)
Read: Anytime
Write: Anytime
Field
Description
0
PROT
Clock Configuration Registers Protection Bit — This bit protects the clock configuration registers from
accidental overwrite (see list of affected registers above).
Writing 0x26 to the CPMUPROT register clears the PROT bit, other write accesses set the PROT bit.
0 Protection of clock configuration registers is disabled.
1 Protection of clock configuration registers is enabled. CPMUSYNR, CPMUREFDIV, CPMUCLKS, CPMUPLL,
CPMUIRCTRIMH/L and CPMUOSC registers are not writable.
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235
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.3.2.23
Reserved Register CPMUTEST2
NOTE
This reserved register is designed for factory test purposes only, and is not
intended for general user access. Writing to this register when in special
mode can alter the S12CPMU’s functionality.
0x02FC
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 7-30. Reserved Register CPMUTEST2
Read: Anytime
Write: Only in special mode
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.4
7.4.1
Functional Description
Phase Locked Loop with Internal Filter (PLL)
The PLL is used to generate a high speed PLLCLK based on a low frequency REFCLK.
The REFCLK is by default the IRCCLK which is trimmed to fIRC1M_TRIM=1MHz.
If using the oscillator (OSCE=1) REFCLK will be based on OSCCLK. For increased flexibility, OSCCLK
can be divided in a range of 1 to 16 to generate the reference frequency REFCLK using the REFDIV[3:0]
bits. Based on the SYNDIV[5:0] bits the PLL generates the VCOCLK by multiplying the reference clock
by a 2, 4, 6,... 126, 128. Based on the POSTDIV[4:0] bits the VCOCLK can be divided in a range of 1,2,
3, 4, 5, 6,... to 32 to generate the PLLCLK.
If oscillator is enabled (OSCE=1)
f OSC
f REF = -----------------------------------( REFDIV + 1 )
If oscillator is disabled (OSCE=0)
f REF = f IRC1M
f VCO = 2 × f REF × ( SYNDIV + 1 )
If PLL is locked (LOCK=1)
f VCO
f PLL = ----------------------------------------( POSTDIV + 1 )
If PLL is not locked (LOCK=0)
f VCO
f PLL = --------------4
If PLL is selected (PLLSEL=1)
f PLL
f bus = ------------2
.
NOTE
Although it is possible to set the dividers to command a very high clock
frequency, do not exceed the specified bus frequency limit for the MCU.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
Several examples of PLL divider settings are shown in Table 7-23. The following rules help to achieve
optimum stability and shortest lock time:
• Use lowest possible fVCO / fREF ratio (SYNDIV value).
• Use highest possible REFCLK frequency fREF.
Table 7-23. Examples of PLL Divider Settings
fosc
REFDIV[3:0]
fREF
REFFRQ[1:0] SYNDIV[5:0]
fVCO
VCOFRQ[1:0] POSTDIV[4:0]
fPLL
fbus
off
$00
1MHz
00
$1F
64MHz
01
$03
16MHz
8MHz
off
$00
1MHz
00
$1F
64MHz
01
$00
64MHz
32MHz
off
$00
1MHz
00
$0F
32MHz
00
$00
32MHz
16MHz
4MHz
$00
4MHz
01
$03
32MHz
01
$00
32MHz
16MHz
The phase detector inside the PLL compares the feedback clock (FBCLK = VCOCLK/(SYNDIV+1)) with
the reference clock (REFCLK = IRC1M or OSCCLK/REFDIV+1)). Correction pulses are generated based
on the phase difference between the two signals. The loop filter alters the DC voltage on the internal filter
capacitor, based on the width and direction of the correction pulse, which leads to a higher or lower VCO
frequency.
The user must select the range of the REFCLK frequency (REFFRQ[1:0] bits) and the range of the
VCOCLK frequency (VCOFRQ[1:0] bits) to ensure that the correct PLL loop bandwidth is set.
The lock detector compares the frequencies of the FBCLK and the REFCLK. Therefore the speed of the
lock detector is directly proportional to the reference clock frequency. The circuit determines the lock
condition based on this comparison.
If PLL LOCK interrupt requests are enabled, the software can wait for an interrupt request and for instance
check the LOCK bit. If interrupt requests are disabled, software can poll the LOCK bit continuously
(during PLL start-up) or at periodic intervals. In either case, only when the LOCK bit is set, the VCOCLK
will have stabilized to the programmed frequency.
• The LOCK bit is a read-only indicator of the locked state of the PLL.
• The LOCK bit is set when the VCO frequency is within the tolerance ∆Lock and is cleared when
the VCO frequency is out of the tolerance ∆unl.
• Interrupt requests can occur if enabled (LOCKIE = 1) when the lock condition changes, toggling
the LOCK bit.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.4.2
Startup from Reset
An example of startup of clock system from Reset is given in Figure 7-31.
Figure 7-31. Startup of clock system after Reset
System
Reset
768 cycles
PLLCLK
fPLL increasing
fVCORST
fPLL=32 MHz
fPLL=16MHz
)(
tlock
LOCK
SYNDIV
$1F (default target fVCO=64MHz)
POSTDIV
$03 (default target fPLL=fVCO/4 = 16MHz)
CPU
reset state
7.4.3
$01
vector fetch, program execution
example change
of POSTDIV
Stop Mode using PLLCLK as Bus Clock
An example of what happens going into Stop Mode and exiting Stop Mode after an interrupt is shown in
Figure 7-32. Disable PLL Lock interrupt (LOCKIE=0) before going into Stop Mode.
Figure 7-32. Stop Mode using PLLCLK as Bus Clock
wakeup
CPU
execution
interrupt
STOP instruction
continue execution
tSTP_REC
PLLCLK
LOCK
tlock
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239
S12 Clock, Reset and Power Management Unit (S12CPMU)
7.4.4
Full Stop Mode using Oscillator Clock as Bus Clock
An example of what happens going into Full Stop Mode and exiting Full Stop Mode after an interrupt is
shown in Figure 7-33.
Disable PLL Lock interrupt (LOCKIE=0) and oscillator status change interrupt (OSCIE=0) before going
into Full Stop Mode.
Figure 7-33. Full Stop Mode using Oscillator Clock as Bus Clock
wakeup
CPU
execution
Core
Clock
PLLCLK
interrupt
STOP instruction
continue execution
tSTP_REC
tlock
OSCCLK
UPOSC
select OSCCLK as Core/Bus Clock by writing PLLSEL to “0”
PLLSEL
automatically set when going into Full Stop Mode
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.4.5
7.4.5.1
External Oscillator
Enabling the External Oscillator
An example of how to use the oscillator as Bus Clock is shown in Figure 7-34.
Figure 7-34. Enabling the External Oscillator
enable external oscillator by writing OSCE bit to one.
OSCE
crystal/resonator starts oscillating
EXTAL
UPOSC flag is set upon successful start of oscillation
UPOSC
OSCCLK
select OSCCLK as Core/Bus Clock by writing PLLSEL to zero
PLLSEL
Core
Clock
based on PLLCLK
based on OSCCLK
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.4.5.2
The Adaptive Oscillator Filter
A spike in the oscillator clock can disturb the function of the modules driven by this clock.
The adaptive Oscillator Filter includes two features:
1. Filter noise (spikes) from the incoming external oscillator clock. The filter function is illustrated in
Figure 7-35.
Figure 7-35. Noise filtered by the Adaptive Oscillator Filter
enable external oscillator
OSCE
configure the Oscillator Filter
OSC
FILT
0
>0
crystal/resonator starts oscillating
EXTAL
LOCK
UPOSC
filtered
filtered
OSCCLK
(filtered)
2. Detect severe noise disturbances on the external oscillator clock, which can not be filtered and
indicate the critical situation to the software by clearing the UPOSC and LOCK status bit and
setting the OSCIF and LOCKIF flag. An example for the detection of critical noise is illustrated in
Figure 7-36.
Figure 7-36. Critical noise detected by the Adaptive Oscillator Filter
enable external oscillator
OSCE
configure the Oscillator Filter
OSC
FILT
0
>0
crystal/resonator starts oscillating
phase shift can not be filtered but detected
EXTAL
LOCK
UPOSC
OSCCLK
(filtered)
NOTE
If the LOCK bit is clear due to severe noise disturbance on the external
oscillator clock the PLLCLK is derived from the VCO clock (with its actual
frequency) divided by four (see also Section 7.3.2.3, “S12CPMU Post
Divider Register (CPMUPOSTDIV))
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S12 Clock, Reset and Power Management Unit (S12CPMU)
The use of the filter function is only possible if the VCOCLK-to-OSCCLK ratio divided by two ((fVCO /
fOSC)/2) is an integer number. This integer value must be written to the OSCFILT[4:0] bits.
If enabled, the oscillator filter is sampling the incoming oscillator clock signal (EXTAL) with the
VCOCLK frequency.
Using VCOCLK, a time window is defined during which an edge of the OSCCLK is expected. In case of
OSCBW = 1 the width of this window is three VCOCLK cycles, if the OSCBW = 0 it is one VCOCLK
cycle.
The noise detection is active for certain combinations of OSCFILT[4:0] and OSCBW bit settings as shown
in Table 7-24
Table 7-24. Noise Detection Settings
OSCFILT[4:0]
OSCBW
Detection
Filter
0
x
disabled
disabled
1
x
disabled
active
2 or 3
0
active
active
1
disabled
active
x
active
active
>=4
NOTE
If the VCOCLK frequency is higher than 25 MHz the wide bandwidth must
be selected (OSCBW = 1).
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.4.6
7.4.6.1
System Clock Configurations
PLL Engaged Internal Mode (PEI)
This mode is the default mode after System Reset or Power-On Reset.
The Bus Clock is based on the PLLCLK, the reference clock for the PLL is internally generated (IRC1M).
The PLL is configured to 64 MHz VCOCLK with POSTDIV set to 0x03. If locked (LOCK=1) this results
in a PLLCLK of 16 MHz and a Bus Clock of 8 MHz. The PLL can be re-configured to other bus
frequencies.
The clock sources for COP and RTI are based on the internal reference clock generator (IRC1M).
7.4.6.2
PLL Engaged External Mode (PEE)
In this mode, the Bus Clock is based on the PLLCLK as well (like PEI). The reference clock for the PLL
is based on the external oscillator. The adaptive spike filter and detection logic which uses the VCOCLK
to filter and qualify the external oscillator clock can be enabled.
The clock sources for COP and RTI can be based on the internal reference clock generator or on the
external oscillator clock.
This mode can be entered from default mode PEI by performing the following steps:
1. Configure the PLL for desired bus frequency.
2. Optionally the adaptive spike filter and detection logic can be enabled by calculating the integer
value for the OSCFIL[4:0] bits and setting the bandwidth (OSCBW) accordingly.
3. Enable the external oscillator (OSCE bit).
4. Wait for the PLL being locked (LOCK = 1) and the oscillator to start-up and additionally being
qualified if the adaptive spike filter is enabled (UPOSC =1).
5. Clear all flags in the CPMUFLG register to be able to detect any future status bit change.
6. Optionally status interrupts can be enabled (CPMUINT register).
Since the adaptive spike filter (filter and detection logic) uses the VCOCLK to continuously filter and
qualify the external oscillator clock, loosing PLL lock status (LOCK=0) means loosing the oscillator status
information as well (UPOSC=0).
The impact of loosing the oscillator status in PEE mode is as follows:
• The PLLCLK is derived from the VCO clock (with its actual frequency) divided by four until the
PLL locks again.
Application software needs to be prepared to deal with the impact of loosing the oscillator status at any
time.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.4.6.3
PLL Bypassed External Mode (PBE)
In this mode, the Bus Clock is based on the external oscillator clock. The reference clock for the PLL is
based on the external oscillator. The adaptive spike filter and detection logic can be enabled which uses
the VCOCLK to filter and qualify the external oscillator clock.
The clock sources for COP and RTI can be based on the internal reference clock generator or on the
external oscillator clock.
This mode can be entered from default mode PEI by performing the following steps:
1. Make sure the PLL configuration is valid
2. Optionally the adaptive spike filter and detection logic can be enabled by calculating the integer
value for the OSCFIL[4:0] bits and setting the bandwidth (OSCBW) accordingly.
3. Enable the external oscillator (OSCE bit)
4. Wait for the PLL being locked (LOCK = 1) and the oscillator to start-up and additionally being
qualified if the adaptive spike filter is enabled (UPOSC =1).
5. Clear all flags in the CPMUFLG register to be able to detect any status bit change.
6. Optionally status interrupts can be enabled (CPMUINT register).
7. Select the Oscillator Clock (OSCCLK) as Bus Clock (PLLSEL=0)
Since the adaptive spike filter (filter and detection logic) uses VCOCLK (from PLL) to continuously filter
and qualify the external oscillator clock, loosing PLL lock status (LOCK=0) means loosing the oscillator
status information as well (UPOSC=0).
The impact of loosing the oscillator status in PBE mode is as follows:
• PLLSEL is set automatically and the Bus Clock is switched back to the PLLCLK.
• The PLLCLK is derived from the VCO clock (with its actual frequency) divided by four until the
PLL locks again.
Application software needs to be prepared to deal with the impact of loosing the oscillator status at any
time.
In the PBE mode, not every noise disturbance can be indicated by bits LOCK and UPOSC (both bits are
based on the Bus Clock domain). There are clock disturbances possible, after which UPOSC and LOCK
both stay asserted while occasional pauses on the filtered OSCCLK and resulting Bus Clock occur. The
spike filter is still functional and protects the Bus Clock from frequency overshoot due to spikes on the
external oscillator clock. The filtered OSCCLK and resulting Bus Clock will pause until the PLL has
stabilized again.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.5
7.5.1
Resets
General
All reset sources are listed in Table 7-25. Refer to MCU specification for related vector addresses and
priorities.
Table 7-25. Reset Summary
7.5.2
Reset Source
Local Enable
Power-On Reset (POR)
None
Low Voltage Reset (LVR)
None
External pin RESET
None
Illegal Address Reset
None
Clock Monitor Reset
OSCE Bit in CPMUOSC register
COP Reset
CR[2:0] in CPMUCOP register
Description of Reset Operation
Upon detection of any reset of Table 7-25, an internal circuit drives the RESET pin low for 512 PLLCLK
cycles. After 512 PLLCLK cycles the RESET pin is released. The reset generator of the S12CPMU waits
for additional 256 PLLCLK cycles and then samples the RESET pin to determine the originating source.
Table 7-26 shows which vector will be fetched.
Table 7-26. Reset Vector Selection
Sampled RESET Pin
(256 cycles after
release)
Oscillator monitor
fail pending
COP
time out
pending
1
0
0
POR
LVR
Illegal Address Reset
External pin RESET
1
1
X
Clock Monitor Reset
1
0
1
COP Reset
0
X
X
POR
LVR
Illegal Address Reset
External pin RESET
Vector Fetch
NOTE
While System Reset is asserted the PLLCLK runs with the frequency
fVCORST.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
The internal reset of the MCU remains asserted while the reset generator completes the 768 PLLCLK
cycles long reset sequence. In case the RESET pin is externally driven low for more than these 768
PLLCLK cycles (External Reset), the internal reset remains asserted longer.
Figure 7-37. RESET Timing
RESET
S12_CPMU drives
RESET pin low
fVCORST
S12_CPMU releases
RESET pin
fVCORST
)
)
PLLCLK
(
(
512 cycles
)
(
256 cycles
possibly
RESET
driven low
externally
7.5.2.1
Clock Monitor Reset
If the external oscillator is enabled (OSCE=1) in case of loss of oscillation or the oscillator frequency is
below the failure assert frequency fCMFA (see device electrical characteristics for values), the S12CPMU
generates a Clock Monitor Reset.In Full Stop Mode the external oscillator and the clock monitor are
disabled.
7.5.2.2
Computer Operating Properly Watchdog (COP) Reset
The COP (free running watchdog timer) enables the user to check that a program is running and
sequencing properly. When the COP is being used, software is responsible for keeping the COP from
timing out. If the COP times out it is an indication that the software is no longer being executed in the
intended sequence; thus COP reset is generated.
The clock source for the COP is either IRCCLK or OSCCLK depending on the setting of the
COPOSCSEL bit. In Stop Mode with PSTP=1 (Pseudo Stop Mode), COPOSCSEL=1 and PCE=1 the COP
continues to run, else the COP counter halts in Stop Mode.
Three control bits in the CPMUCOP register allow selection of seven COP time-out periods.
When COP is enabled, the program must write $55 and $AA (in this order) to the CPMUARMCOP
register during the selected time-out period. Once this is done, the COP time-out period is restarted. If the
program fails to do this and the COP times out, a COP reset is generated. Also, if any value other than $55
or $AA is written, a COP reset generated.
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S12 Clock, Reset and Power Management Unit (S12CPMU)
Windowed COP operation is enabled by setting WCOP in the CPMUCOP register. In this mode, writes to
the CPMUARMCOP register to clear the COP timer must occur in the last 25% of the selected time-out
period. A premature write will immediately reset the part.
7.5.3
Power-On Reset (POR)
The on-chip POR circuitry detects when the internal supply VDD drops below an appropriate voltage level
(voltage level not specified in this document because this supply is not visible on device pins). POR is
deasserted, if the internal supply VDD exceeds an appropriate voltage level (voltage level not specified in
this document because this supply is not visible on device pins).
7.5.4
Low-Voltage Reset (LVR)
The on-chip LVR circuitry detects when one of the supply voltages VDD, VDDF or VDDX drops below an
appropriate voltage level. If LVR is deasserted the MCU is fully operational at the specified maximum
speed.The LVR assert and deassert levels for the supply voltage VDDX are VLVRXA and VLVRXD and are
specified in the device Reference Manual.
7.6
Interrupts
The interrupt/reset vectors requested by the S12CPMU are listed in Table 7-27. Refer to MCU
specification for related vector addresses and priorities.
Table 7-27. S12CPMU Interrupt Vectors
Interrupt Source
CCR
Mask
Local Enable
RTI time-out interrupt
I bit
CPMUINT (RTIE)
PLL lock interrupt
I bit
CPMUINT (LOCKIE)
Oscillator status
interrupt
I bit
CPMUINT (OSCIE)
Low voltage interrupt
I bit
CPMULVCTL (LVIE)
High temperature
interrupt
I bit
CPMUHTCTL (HTIE)
Autonomous
Periodical Interrupt
I bit
CPMUAPICTL (APIE)
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S12 Clock, Reset and Power Management Unit (S12CPMU)
7.6.1
7.6.1.1
Description of Interrupt Operation
Real Time Interrupt (RTI)
The clock source for the RTI is either IRCCLK or OSCCLK depending on the setting of the RTIOSCSEL
bit. In Stop Mode with PSTP=1 (Pseudo Stop Mode), RTIOSCSEL=1 and PRE=1 the RTI continues to
run, else the RTI counter halts in Stop Mode.
The RTI can be used to generate hardware interrupts at a fixed periodic rate. If enabled (by setting
RTIE=1), this interrupt will occur at the rate selected by the CPMURTI register. At the end of the RTI
time-out period the RTIF flag is set to one and a new RTI time-out period starts immediately.
A write to the CPMURTI register restarts the RTI time-out period.
7.6.1.2
PLL Lock Interrupt
The S12CPMU generates a PLL Lock interrupt when the lock condition (LOCK status bit) of the PLL
changes, either from a locked state to an unlocked state or vice versa. Lock interrupts are locally disabled
by setting the LOCKIE bit to zero. The PLL Lock interrupt flag (LOCKIF) is set to 1 when the lock
condition has changed, and is cleared to 0 by writing a 1 to the LOCKIF bit.
7.6.1.3
Oscillator Status Interrupt
The Oscillator Filter contains two different features:
1. Filter spikes of the external oscillator clock.
2. Qualify the external oscillator clock.
When the OSCE bit is 0, then UPOSC stays 0. When OSCE=1 and OSCFILT = 0, then the filter is
transparent and no spikes are filtered. The UPOSC bit is then set after the LOCK bit is set.
Upon detection of a status change (UPOSC), that is an unqualified oscillation becomes qualified or vice
versa, the OSCIF flag is set. Going into Full Stop Mode or disabling the oscillator can also cause a status
change of UPOSC.
Also, since the oscillator filter is based on the PLLCLK, any change in PLL configuration or any other
event which causes the PLL lock status to be cleared leads to a loss of the oscillator status information as
well (UPOSC=0).
Oscillator status change interrupts are locally enabled with the OSCIE bit.
NOTE
loosing the oscillator status (UPOSC=0) affects the clock configuration of
the system1. This needs to be dealt with in application software.
1. For details please refer to “7.4.6 System Clock Configurations”
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7.6.1.4
Low-Voltage Interrupt (LVI)
In FPM the input voltage VDDA is monitored. Whenever VDDA drops below level VLVIA, the status bit
LVDS is set to 1. On the other hand, LVDS is reset to 0 when VDDA rises above level VLVID. An interrupt,
indicated by flag LVIF = 1, is triggered by any change of the status bit LVDS if interrupt enable bit LVIE
= 1.
7.6.1.5
HTI - High Temperature Interrupt
In FPM the junction temperature TJ is monitored. Whenever TJ exceeds level THTIA the status bit HTDS
is set to 1. Vice versa, HTDS is reset to 0 when TJ get below level THTID. An interrupt, indicated by flag
HTIF = 1, is triggered by any change of the status bit HTDS, if interrupt enable bit HTIE = 1.
7.6.1.6
Autonomous Periodical Interrupt (API)
The API sub-block can generate periodical interrupts independent of the clock source of the MCU. To
enable the timer, the bit APIFE needs to be set.
The API timer is either clocked by a trimmable internal RC oscillator (ACLK) or the Bus Clock. Timer
operation will freeze when MCU clock source is selected and Bus Clock is turned off. The clock source
can be selected with bit APICLK. APICLK can only be written when APIFE is not set.
The APIR[15:0] bits determine the interrupt period. APIR[15:0] can only be written when APIFE is
cleared. As soon as APIFE is set, the timer starts running for the period selected by APIR[15:0] bits. When
the configured time has elapsed, the flag APIF is set. An interrupt, indicated by flag APIF = 1, is triggered
if interrupt enable bit APIE = 1. The timer is re-started automatically again after it has set APIF.
The procedure to change APICLK or APIR[15:0] is first to clear APIFE, then write to APICLK or
APIR[15:0], and afterwards set APIFE.
The API Trimming bits APITR[5:0] must be set so the minimum period equals 0.2 ms if stable frequency
is desired.
See Table 7-17 for the trimming effect of APITR.
NOTE
The first period after enabling the counter by APIFE might be reduced by
API start up delay tsdel.
It is possible to generate with the API a waveform at the external pin API_EXTCLK by setting APIFE and
enabling the external access with setting APIEA.
7.7
Initialization/Application Information
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Chapter 8
Freescale’s Scalable Controller Area Network
(S12MSCANV3)
Table 8-1. Revision History
Revision
Number
Revision Date
V03.08
07 Mar 2006
V03.09
04 May 2007
8.3.2.11/8-268
- Corrected mnemonics of code example in CANTBSEL register description
V03.10
19 Aug 2008
8.4.7.4/8-302
8.4.4.5/8-296
8.2/8-253
- Corrected wake-up description
- Relocated initialization section
- Added note to external pin descriptions for use with integrated physical layer
- Minor corrections
8.1
Sections
Affected
Description of Changes
- Internal updates only.
Introduction
Freescale’s scalable controller area network (S12MSCANV3) definition is based on the MSCAN12
definition, which is the specific implementation of the MSCAN concept targeted for the M68HC12
microcontroller family.
The module is a communication controller implementing the CAN 2.0A/B protocol as defined in the
Bosch specification dated September 1991. For users to fully understand the MSCAN specification, it is
recommended that the Bosch specification be read first to familiarize the reader with the terms and
concepts contained within this document.
Though not exclusively intended for automotive applications, CAN protocol is designed to meet the
specific requirements of a vehicle serial data bus: real-time processing, reliable operation in the EMI
environment of a vehicle, cost-effectiveness, and required bandwidth.
MSCAN uses an advanced buffer arrangement resulting in predictable real-time behavior and simplified
application software.
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8.1.1
Glossary
Table 8-2. Terminology
ACK
Acknowledge of CAN message
CAN
Controller Area Network
CRC
Cyclic Redundancy Code
EOF
End of Frame
FIFO
First-In-First-Out Memory
IFS
Inter-Frame Sequence
SOF
Start of Frame
CPU bus
CPU related read/write data bus
CAN bus
CAN protocol related serial bus
oscillator clock
8.1.2
Direct clock from external oscillator
bus clock
CPU bus realated clock
CAN clock
CAN protocol related clock
Block Diagram
MSCAN
Oscillator Clock
Bus Clock
CANCLK
MUX
Presc.
Tq Clk
Receive/
Transmit
Engine
RXCAN
TXCAN
Transmit Interrupt Req.
Receive Interrupt Req.
Errors Interrupt Req.
Message
Filtering
and
Buffering
Control
and
Status
Wake-Up Interrupt Req.
Configuration
Registers
Wake-Up
Low Pass Filter
Figure 8-1. MSCAN Block Diagram
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8.1.3
Features
The basic features of the MSCAN are as follows:
• Implementation of the CAN protocol — Version 2.0A/B
— Standard and extended data frames
— Zero to eight bytes data length
— Programmable bit rate up to 1 Mbps1
— Support for remote frames
• Five receive buffers with FIFO storage scheme
• Three transmit buffers with internal prioritization using a “local priority” concept
• Flexible maskable identifier filter supports two full-size (32-bit) extended identifier filters, or four
16-bit filters, or eight 8-bit filters
• Programmable wakeup functionality with integrated low-pass filter
• Programmable loopback mode supports self-test operation
• Programmable listen-only mode for monitoring of CAN bus
• Programmable bus-off recovery functionality
• Separate signalling and interrupt capabilities for all CAN receiver and transmitter error states
(warning, error passive, bus-off)
• Programmable MSCAN clock source either bus clock or oscillator clock
• Internal timer for time-stamping of received and transmitted messages
• Three low-power modes: sleep, power down, and MSCAN enable
• Global initialization of configuration registers
8.1.4
Modes of Operation
For a description of the specific MSCAN modes and the module operation related to the system operating
modes refer to Section 8.4.4, “Modes of Operation”.
8.2
External Signal Description
The MSCAN uses two external pins.
NOTE
On MCUs with an integrated CAN physical interface (transceiver) the
MSCAN interface is connected internally to the transceiver interface. In
these cases the external availability of signals TXCAN and RXCAN is
optional.
8.2.1
RXCAN — CAN Receiver Input Pin
RXCAN is the MSCAN receiver input pin.
1. Depending on the actual bit timing and the clock jitter of the PLL.
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8.2.2
TXCAN — CAN Transmitter Output Pin
TXCAN is the MSCAN transmitter output pin. The TXCAN output pin represents the logic level on the
CAN bus:
0 = Dominant state
1 = Recessive state
8.2.3
CAN System
A typical CAN system with MSCAN is shown in Figure 8-2. Each CAN station is connected physically
to the CAN bus lines through a transceiver device. The transceiver is capable of driving the large current
needed for the CAN bus and has current protection against defective CAN or defective stations.
CAN node 2
CAN node 1
CAN node n
MCU
CAN Controller
(MSCAN)
TXCAN
RXCAN
Transceiver
CANH
CANL
CAN Bus
Figure 8-2. CAN System
8.3
Memory Map and Register Definition
This section provides a detailed description of all registers accessible in the MSCAN.
8.3.1
Module Memory Map
Figure 8-3 gives an overview on all registers and their individual bits in the MSCAN memory map. The
register address results from the addition of base address and address offset. The base address is
determined at the MCU level and can be found in the MCU memory map description. The address offset
is defined at the module level.
The MSCAN occupies 64 bytes in the memory space. The base address of the MSCAN module is
determined at the MCU level when the MCU is defined. The register decode map is fixed and begins at the
first address of the module address offset.
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The detailed register descriptions follow in the order they appear in the register map.
Register
Name
Bit 7
0x0000
CANCTL0
R
0x0001
CANCTL1
R
0x0002
CANBTR0
R
0x0003
CANBTR1
R
0x0004
CANRFLG
R
0x0005
CANRIER
R
0x0006
CANTFLG
R
W
W
W
W
W
W
RXACT
5
CSWAI
4
SYNCH
3
2
1
Bit 0
TIME
WUPE
SLPRQ
INITRQ
SLPAK
INITAK
CANE
CLKSRC
LOOPB
LISTEN
BORM
WUPM
SJW1
SJW0
BRP5
BRP4
BRP3
BRP2
BRP1
BRP0
SAMP
TSEG22
TSEG21
TSEG20
TSEG13
TSEG12
TSEG11
TSEG10
WUPIF
CSCIF
RSTAT1
RSTAT0
TSTAT1
TSTAT0
OVRIF
RXF
WUPIE
CSCIE
RSTATE1
RSTATE0
TSTATE1
TSTATE0
OVRIE
RXFIE
0
0
0
0
0
TXE2
TXE1
TXE0
0
0
0
0
0
TXEIE2
TXEIE1
TXEIE0
0
0
0
0
0
ABTRQ2
ABTRQ1
ABTRQ0
0
0
0
0
0
ABTAK2
ABTAK1
ABTAK0
0
0
0
0
0
TX2
TX1
TX0
0
0
IDAM1
IDAM0
0
IDHIT2
IDHIT1
IDHIT0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
0x0007
CANTIER
R
0x0008
CANTARQ
R
0x0009
CANTAAK
RXFRM
6
W
W
R
W
0x000A
CANTBSEL
R
W
0x000B
CANIDAC
W
R
0x000C
Reserved
R
0x000D
CANMISC
R
W
W
BOHOLD
= Unimplemented or Reserved
Figure 8-3. MSCAN Register Summary
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Register
Name
0x000E
CANRXERR
R
0x000F
CANTXERR
R
0x0010–0x0013
CANIDAR0–3
R
0x0014–0x0017
CANIDMRx
R
0x0018–0x001B
CANIDAR4–7
R
0x001C–0x001F
CANIDMR4–7
R
0x0020–0x002F
CANRXFG
R
0x0030–0x003F
CANTXFG
R
Bit 7
6
5
4
3
2
1
Bit 0
RXERR7
RXERR6
RXERR5
RXERR4
RXERR3
RXERR2
RXERR1
RXERR0
TXERR7
TXERR6
TXERR5
TXERR4
TXERR3
TXERR2
TXERR1
TXERR0
AC7
AC6
AC5
AC4
AC3
AC2
AC1
AC0
AM7
AM6
AM5
AM4
AM3
AM2
AM1
AM0
AC7
AC6
AC5
AC4
AC3
AC2
AC1
AC0
AM7
AM6
AM5
AM4
AM3
AM2
AM1
AM0
W
W
W
W
W
W
W
W
See Section 8.3.3, “Programmer’s Model of Message Storage”
See Section 8.3.3, “Programmer’s Model of Message Storage”
= Unimplemented or Reserved
Figure 8-3. MSCAN Register Summary (continued)
8.3.2
Register Descriptions
This section describes in detail all the registers and register bits in the MSCAN module. Each description
includes a standard register diagram with an associated figure number. Details of register bit and field
function follow the register diagrams, in bit order. All bits of all registers in this module are completely
synchronous to internal clocks during a register read.
8.3.2.1
MSCAN Control Register 0 (CANCTL0)
The CANCTL0 register provides various control bits of the MSCAN module as described below.
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Access: User read/write(1)
Module Base + 0x0000
7
R
6
5
RXACT
RXFRM
4
3
2
1
0
TIME
WUPE
SLPRQ
INITRQ
0
0
0
1
SYNCH
CSWAI
W
Reset:
0
0
0
0
= Unimplemented
Figure 8-4. MSCAN Control Register 0 (CANCTL0)
1. Read: Anytime
Write: Anytime when out of initialization mode; exceptions are read-only RXACT and SYNCH, RXFRM (which is set by the
module only), and INITRQ (which is also writable in initialization mode)
NOTE
The CANCTL0 register, except WUPE, INITRQ, and SLPRQ, is held in the
reset state when the initialization mode is active (INITRQ = 1 and
INITAK = 1). This register is writable again as soon as the initialization
mode is exited (INITRQ = 0 and INITAK = 0).
Table 8-3. CANCTL0 Register Field Descriptions
Field
Description
7
RXFRM(1)
Received Frame Flag — This bit is read and clear only. It is set when a receiver has received a valid message
correctly, independently of the filter configuration. After it is set, it remains set until cleared by software or reset.
Clearing is done by writing a 1. Writing a 0 is ignored. This bit is not valid in loopback mode.
0 No valid message was received since last clearing this flag
1 A valid message was received since last clearing of this flag
6
RXACT
Receiver Active Status — This read-only flag indicates the MSCAN is receiving a message. The flag is
controlled by the receiver front end. This bit is not valid in loopback mode.
0 MSCAN is transmitting or idle2
1 MSCAN is receiving a message (including when arbitration is lost)(2)
5
CSWAI(3)
CAN Stops in Wait Mode — Enabling this bit allows for lower power consumption in wait mode by disabling all
the clocks at the CPU bus interface to the MSCAN module.
0 The module is not affected during wait mode
1 The module ceases to be clocked during wait mode
4
SYNCH
Synchronized Status — This read-only flag indicates whether the MSCAN is synchronized to the CAN bus and
able to participate in the communication process. It is set and cleared by the MSCAN.
0 MSCAN is not synchronized to the CAN bus
1 MSCAN is synchronized to the CAN bus
3
TIME
Timer Enable — This bit activates an internal 16-bit wide free running timer which is clocked by the bit clock rate.
If the timer is enabled, a 16-bit time stamp will be assigned to each transmitted/received message within the
active TX/RX buffer. Right after the EOF of a valid message on the CAN bus, the time stamp is written to the
highest bytes (0x000E, 0x000F) in the appropriate buffer (see Section 8.3.3, “Programmer’s Model of Message
Storage”). The internal timer is reset (all bits set to 0) when disabled. This bit is held low in initialization mode.
0 Disable internal MSCAN timer
1 Enable internal MSCAN timer
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Table 8-3. CANCTL0 Register Field Descriptions (continued)
Field
Description
2
WUPE(4)
Wake-Up Enable — This configuration bit allows the MSCAN to restart from sleep mode or from power down
mode (entered from sleep) when traffic on CAN is detected (see Section 8.4.5.5, “MSCAN Sleep Mode”). This
bit must be configured before sleep mode entry for the selected function to take effect.
0 Wake-up disabled — The MSCAN ignores traffic on CAN
1 Wake-up enabled — The MSCAN is able to restart
1
SLPRQ(5)
Sleep Mode Request — This bit requests the MSCAN to enter sleep mode, which is an internal power saving
mode (see Section 8.4.5.5, “MSCAN Sleep Mode”). The sleep mode request is serviced when the CAN bus is
idle, i.e., the module is not receiving a message and all transmit buffers are empty. The module indicates entry
to sleep mode by setting SLPAK = 1 (see Section 8.3.2.2, “MSCAN Control Register 1 (CANCTL1)”). SLPRQ
cannot be set while the WUPIF flag is set (see Section 8.3.2.5, “MSCAN Receiver Flag Register (CANRFLG)”).
Sleep mode will be active until SLPRQ is cleared by the CPU or, depending on the setting of WUPE, the MSCAN
detects activity on the CAN bus and clears SLPRQ itself.
0 Running — The MSCAN functions normally
1 Sleep mode request — The MSCAN enters sleep mode when CAN bus idle
0
Initialization Mode Request — When this bit is set by the CPU, the MSCAN skips to initialization mode (see
INITRQ(6),(7) Section 8.4.4.5, “MSCAN Initialization Mode”). Any ongoing transmission or reception is aborted and
synchronization to the CAN bus is lost. The module indicates entry to initialization mode by setting INITAK = 1
(Section 8.3.2.2, “MSCAN Control Register 1 (CANCTL1)”).
The following registers enter their hard reset state and restore their default values: CANCTL0(8), CANRFLG(9),
CANRIER(10), CANTFLG, CANTIER, CANTARQ, CANTAAK, and CANTBSEL.
The registers CANCTL1, CANBTR0, CANBTR1, CANIDAC, CANIDAR0-7, and CANIDMR0-7 can only be
written by the CPU when the MSCAN is in initialization mode (INITRQ = 1 and INITAK = 1). The values of the
error counters are not affected by initialization mode.
When this bit is cleared by the CPU, the MSCAN restarts and then tries to synchronize to the CAN bus. If the
MSCAN is not in bus-off state, it synchronizes after 11 consecutive recessive bits on the CAN bus; if the MSCAN
is in bus-off state, it continues to wait for 128 occurrences of 11 consecutive recessive bits.
Writing to other bits in CANCTL0, CANRFLG, CANRIER, CANTFLG, or CANTIER must be done only after
initialization mode is exited, which is INITRQ = 0 and INITAK = 0.
0 Normal operation
1 MSCAN in initialization mode
1. The MSCAN must be in normal mode for this bit to become set.
2. See the Bosch CAN 2.0A/B specification for a detailed definition of transmitter and receiver states.
3. In order to protect from accidentally violating the CAN protocol, TXCAN is immediately forced to a recessive state when the
CPU enters wait (CSWAI = 1) or stop mode (see Section 8.4.5.2, “Operation in Wait Mode” and Section 8.4.5.3, “Operation in
Stop Mode”).
4. The CPU has to make sure that the WUPE register and the WUPIE wake-up interrupt enable register (see Section 8.3.2.6,
“MSCAN Receiver Interrupt Enable Register (CANRIER)) is enabled, if the recovery mechanism from stop or wait is required.
5. The CPU cannot clear SLPRQ before the MSCAN has entered sleep mode (SLPRQ = 1 and SLPAK = 1).
6. The CPU cannot clear INITRQ before the MSCAN has entered initialization mode (INITRQ = 1 and INITAK = 1).
7. In order to protect from accidentally violating the CAN protocol, TXCAN is immediately forced to a recessive state when the
initialization mode is requested by the CPU. Thus, the recommended procedure is to bring the MSCAN into sleep mode
(SLPRQ = 1 and SLPAK = 1) before requesting initialization mode.
8. Not including WUPE, INITRQ, and SLPRQ.
9. TSTAT1 and TSTAT0 are not affected by initialization mode.
10. RSTAT1 and RSTAT0 are not affected by initialization mode.
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8.3.2.2
MSCAN Control Register 1 (CANCTL1)
The CANCTL1 register provides various control bits and handshake status information of the MSCAN
module as described below.
Access: User read/write(1)
Module Base + 0x0001
7
6
5
4
3
2
CANE
CLKSRC
LOOPB
LISTEN
BORM
WUPM
0
0
0
1
0
0
R
1
0
SLPAK
INITAK
0
1
W
Reset:
= Unimplemented
Figure 8-5. MSCAN Control Register 1 (CANCTL1)
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1); CANE is write once
Table 8-4. CANCTL1 Register Field Descriptions
Field
7
CANE
Description
MSCAN Enable
0 MSCAN module is disabled
1 MSCAN module is enabled
6
CLKSRC
MSCAN Clock Source — This bit defines the clock source for the MSCAN module (only for systems with a clock
generation module; Section 8.4.3.2, “Clock System,” and Section Figure 8-43., “MSCAN Clocking Scheme,”).
0 MSCAN clock source is the oscillator clock
1 MSCAN clock source is the bus clock
5
LOOPB
Loopback Self Test Mode — When this bit is set, the MSCAN performs an internal loopback which can be used
for self test operation. The bit stream output of the transmitter is fed back to the receiver internally. The RXCAN
input is ignored and the TXCAN output goes to the recessive state (logic 1). The MSCAN behaves as it does
normally when transmitting and treats its own transmitted message as a message received from a remote node.
In this state, the MSCAN ignores the bit sent during the ACK slot in the CAN frame acknowledge field to ensure
proper reception of its own message. Both transmit and receive interrupts are generated.
0 Loopback self test disabled
1 Loopback self test enabled
4
LISTEN
Listen Only Mode — This bit configures the MSCAN as a CAN bus monitor. When LISTEN is set, all valid CAN
messages with matching ID are received, but no acknowledgement or error frames are sent out (see
Section 8.4.4.4, “Listen-Only Mode”). In addition, the error counters are frozen. Listen only mode supports
applications which require “hot plugging” or throughput analysis. The MSCAN is unable to transmit any
messages when listen only mode is active.
0 Normal operation
1 Listen only mode activated
3
BORM
Bus-Off Recovery Mode — This bits configures the bus-off state recovery mode of the MSCAN. Refer to
Section 8.5.2, “Bus-Off Recovery,” for details.
0 Automatic bus-off recovery (see Bosch CAN 2.0A/B protocol specification)
1 Bus-off recovery upon user request
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Table 8-4. CANCTL1 Register Field Descriptions (continued)
Field
Description
2
WUPM
Wake-Up Mode — If WUPE in CANCTL0 is enabled, this bit defines whether the integrated low-pass filter is
applied to protect the MSCAN from spurious wake-up (see Section 8.4.5.5, “MSCAN Sleep Mode”).
0 MSCAN wakes up on any dominant level on the CAN bus
1 MSCAN wakes up only in case of a dominant pulse on the CAN bus that has a length of Twup
1
SLPAK
Sleep Mode Acknowledge — This flag indicates whether the MSCAN module has entered sleep mode (see
Section 8.4.5.5, “MSCAN Sleep Mode”). It is used as a handshake flag for the SLPRQ sleep mode request.
Sleep mode is active when SLPRQ = 1 and SLPAK = 1. Depending on the setting of WUPE, the MSCAN will
clear the flag if it detects activity on the CAN bus while in sleep mode.
0 Running — The MSCAN operates normally
1 Sleep mode active — The MSCAN has entered sleep mode
0
INITAK
Initialization Mode Acknowledge — This flag indicates whether the MSCAN module is in initialization mode
(see Section 8.4.4.5, “MSCAN Initialization Mode”). It is used as a handshake flag for the INITRQ initialization
mode request. Initialization mode is active when INITRQ = 1 and INITAK = 1. The registers CANCTL1,
CANBTR0, CANBTR1, CANIDAC, CANIDAR0–CANIDAR7, and CANIDMR0–CANIDMR7 can be written only by
the CPU when the MSCAN is in initialization mode.
0 Running — The MSCAN operates normally
1 Initialization mode active — The MSCAN has entered initialization mode
8.3.2.3
MSCAN Bus Timing Register 0 (CANBTR0)
The CANBTR0 register configures various CAN bus timing parameters of the MSCAN module.
Access: User read/write(1)
Module Base + 0x0002
7
6
5
4
3
2
1
0
SJW1
SJW0
BRP5
BRP4
BRP3
BRP2
BRP1
BRP0
0
0
0
0
0
0
0
0
R
W
Reset:
Figure 8-6. MSCAN Bus Timing Register 0 (CANBTR0)
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
Table 8-5. CANBTR0 Register Field Descriptions
Field
Description
7-6
SJW[1:0]
Synchronization Jump Width — The synchronization jump width defines the maximum number of time quanta
(Tq) clock cycles a bit can be shortened or lengthened to achieve resynchronization to data transitions on the
CAN bus (see Table 8-6).
5-0
BRP[5:0]
Baud Rate Prescaler — These bits determine the time quanta (Tq) clock which is used to build up the bit timing
(see Table 8-7).
Table 8-6. Synchronization Jump Width
SJW1
SJW0
Synchronization Jump Width
0
0
1 Tq clock cycle
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Table 8-6. Synchronization Jump Width (continued)
SJW1
SJW0
Synchronization Jump Width
0
1
2 Tq clock cycles
1
0
3 Tq clock cycles
1
1
4 Tq clock cycles
Table 8-7. Baud Rate Prescaler
8.3.2.4
BRP5
BRP4
BRP3
BRP2
BRP1
BRP0
Prescaler value (P)
0
0
0
0
0
0
1
0
0
0
0
0
1
2
0
0
0
0
1
0
3
0
0
0
0
1
1
4
:
:
:
:
:
:
:
1
1
1
1
1
1
64
MSCAN Bus Timing Register 1 (CANBTR1)
The CANBTR1 register configures various CAN bus timing parameters of the MSCAN module.
Access: User read/write(1)
Module Base + 0x0003
7
6
5
4
3
2
1
0
SAMP
TSEG22
TSEG21
TSEG20
TSEG13
TSEG12
TSEG11
TSEG10
0
0
0
0
0
0
0
0
R
W
Reset:
Figure 8-7. MSCAN Bus Timing Register 1 (CANBTR1)
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
Table 8-8. CANBTR1 Register Field Descriptions
Field
Description
7
SAMP
Sampling — This bit determines the number of CAN bus samples taken per bit time.
0 One sample per bit.
1 Three samples per bit(1).
If SAMP = 0, the resulting bit value is equal to the value of the single bit positioned at the sample point. If
SAMP = 1, the resulting bit value is determined by using majority rule on the three total samples. For higher bit
rates, it is recommended that only one sample is taken per bit time (SAMP = 0).
6-4
Time Segment 2 — Time segments within the bit time fix the number of clock cycles per bit time and the location
TSEG2[2:0] of the sample point (see Figure 8-44). Time segment 2 (TSEG2) values are programmable as shown in Table 89.
3-0
Time Segment 1 — Time segments within the bit time fix the number of clock cycles per bit time and the location
TSEG1[3:0] of the sample point (see Figure 8-44). Time segment 1 (TSEG1) values are programmable as shown in Table 810.
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1. In this case, PHASE_SEG1 must be at least 2 time quanta (Tq).
Table 8-9. Time Segment 2 Values
TSEG22
TSEG21
TSEG20
Time Segment 2
0
0
0
1 Tq clock cycle(1)
0
0
1
2 Tq clock cycles
:
:
:
:
1
1
0
7 Tq clock cycles
1
1
1
8 Tq clock cycles
1. This setting is not valid. Please refer to Table 8-37 for valid settings.
Table 8-10. Time Segment 1 Values
TSEG13
TSEG12
TSEG11
TSEG10
Time segment 1
0
0
0
0
1 Tq clock cycle(1)
0
0
0
1
2 Tq clock cycles1
0
0
1
0
3 Tq clock cycles1
0
0
1
1
4 Tq clock cycles
:
:
:
:
:
1
1
1
0
15 Tq clock cycles
1
1
1
1
16 Tq clock cycles
1. This setting is not valid. Please refer to Table 8-37 for valid settings.
The bit time is determined by the oscillator frequency, the baud rate prescaler, and the number of time
quanta (Tq) clock cycles per bit (as shown in Table 8-9 and Table 8-10).
Eqn. 8-1
( Prescaler value )
Bit Time = ------------------------------------------------------ • ( 1 + TimeSegment1 + TimeSegment2 )
f CANCLK
8.3.2.5
MSCAN Receiver Flag Register (CANRFLG)
A flag can be cleared only by software (writing a 1 to the corresponding bit position) when the condition
which caused the setting is no longer valid. Every flag has an associated interrupt enable bit in the
CANRIER register.
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Access: User read/write(1)
Module Base + 0x0004
7
6
WUPIF
CSCIF
0
0
R
5
4
3
2
RSTAT1
RSTAT0
TSTAT1
TSTAT0
1
0
OVRIF
RXF
0
0
W
Reset:
0
0
0
0
= Unimplemented
Figure 8-8. MSCAN Receiver Flag Register (CANRFLG)
1. Read: Anytime
Write: Anytime when not in initialization mode, except RSTAT[1:0] and TSTAT[1:0] flags which are read-only; write of 1 clears
flag; write of 0 is ignored
NOTE
The CANRFLG register is held in the reset state1 when the initialization
mode is active (INITRQ = 1 and INITAK = 1). This register is writable again
as soon as the initialization mode is exited (INITRQ = 0 and INITAK = 0).
Table 8-11. CANRFLG Register Field Descriptions
Field
Description
7
WUPIF
Wake-Up Interrupt Flag — If the MSCAN detects CAN bus activity while in sleep mode (see Section 8.4.5.5,
“MSCAN Sleep Mode,”) and WUPE = 1 in CANTCTL0 (see Section 8.3.2.1, “MSCAN Control Register 0
(CANCTL0)”), the module will set WUPIF. If not masked, a wake-up interrupt is pending while this flag is set.
0
No wake-up activity observed while in sleep mode
1
MSCAN detected activity on the CAN bus and requested wake-up
6
CSCIF
CAN Status Change Interrupt Flag — This flag is set when the MSCAN changes its current CAN bus status
due to the actual value of the transmit error counter (TEC) and the receive error counter (REC). An additional 4bit (RSTAT[1:0], TSTAT[1:0]) status register, which is split into separate sections for TEC/REC, informs the
system on the actual CAN bus status (see Section 8.3.2.6, “MSCAN Receiver Interrupt Enable Register
(CANRIER)”). If not masked, an error interrupt is pending while this flag is set. CSCIF provides a blocking
interrupt. That guarantees that the receiver/transmitter status bits (RSTAT/TSTAT) are only updated when no
CAN status change interrupt is pending. If the TECs/RECs change their current value after the CSCIF is
asserted, which would cause an additional state change in the RSTAT/TSTAT bits, these bits keep their status
until the current CSCIF interrupt is cleared again.
0
No change in CAN bus status occurred since last interrupt
1
MSCAN changed current CAN bus status
5-4
RSTAT[1:0]
Receiver Status Bits — The values of the error counters control the actual CAN bus status of the MSCAN. As
soon as the status change interrupt flag (CSCIF) is set, these bits indicate the appropriate receiver related CAN
bus status of the MSCAN. The coding for the bits RSTAT1, RSTAT0 is:
00
RxOK: 0 ≤ receive error counter ≤ 96
01
RxWRN: 96 < receive error counter ≤ 127
10
RxERR: 127 < receive error counter
11
Bus-off(1): transmit error counter > 255
1. The RSTAT[1:0], TSTAT[1:0] bits are not affected by initialization mode.
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Table 8-11. CANRFLG Register Field Descriptions (continued)
Field
Description
3-2
TSTAT[1:0]
Transmitter Status Bits — The values of the error counters control the actual CAN bus status of the MSCAN.
As soon as the status change interrupt flag (CSCIF) is set, these bits indicate the appropriate transmitter related
CAN bus status of the MSCAN. The coding for the bits TSTAT1, TSTAT0 is:
00
TxOK: 0 ≤ transmit error counter ≤ 96
01
TxWRN: 96 < transmit error counter ≤ 127
10
TxERR: 127 < transmit error counter ≤ 255
11
Bus-Off: transmit error counter > 255
1
OVRIF
Overrun Interrupt Flag — This flag is set when a data overrun condition occurs. If not masked, an error interrupt
is pending while this flag is set.
0
No data overrun condition
1
A data overrun detected
0
RXF(2)
Receive Buffer Full Flag — RXF is set by the MSCAN when a new message is shifted in the receiver FIFO.
This flag indicates whether the shifted buffer is loaded with a correctly received message (matching identifier,
matching cyclic redundancy code (CRC) and no other errors detected). After the CPU has read that message
from the RxFG buffer in the receiver FIFO, the RXF flag must be cleared to release the buffer. A set RXF flag
prohibits the shifting of the next FIFO entry into the foreground buffer (RxFG). If not masked, a receive interrupt
is pending while this flag is set.
0
No new message available within the RxFG
1
The receiver FIFO is not empty. A new message is available in the RxFG
1. Redundant Information for the most critical CAN bus status which is “bus-off”. This only occurs if the Tx error counter exceeds
a number of 255 errors. Bus-off affects the receiver state. As soon as the transmitter leaves its bus-off state the receiver state
skips to RxOK too. Refer also to TSTAT[1:0] coding in this register.
2. To ensure data integrity, do not read the receive buffer registers while the RXF flag is cleared. For MCUs with dual CPUs,
reading the receive buffer registers while the RXF flag is cleared may result in a CPU fault condition.
8.3.2.6
MSCAN Receiver Interrupt Enable Register (CANRIER)
This register contains the interrupt enable bits for the interrupt flags described in the CANRFLG register.
Access: User read/write(1)
Module Base + 0x0005
7
6
5
4
3
2
1
0
WUPIE
CSCIE
RSTATE1
RSTATE0
TSTATE1
TSTATE0
OVRIE
RXFIE
0
0
0
0
0
0
0
0
R
W
Reset:
Figure 8-9. MSCAN Receiver Interrupt Enable Register (CANRIER)
1. Read: Anytime
Write: Anytime when not in initialization mode
NOTE
The CANRIER register is held in the reset state when the initialization mode
is active (INITRQ=1 and INITAK=1). This register is writable when not in
initialization mode (INITRQ=0 and INITAK=0).
The RSTATE[1:0], TSTATE[1:0] bits are not affected by initialization
mode.
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Table 8-12. CANRIER Register Field Descriptions
Field
7
WUPIE(1)
6
CSCIE
Description
Wake-Up Interrupt Enable
0 No interrupt request is generated from this event.
1 A wake-up event causes a Wake-Up interrupt request.
CAN Status Change Interrupt Enable
0 No interrupt request is generated from this event.
1 A CAN Status Change event causes an error interrupt request.
5-4
Receiver Status Change Enable — These RSTAT enable bits control the sensitivity level in which receiver state
RSTATE[1:0] changes are causing CSCIF interrupts. Independent of the chosen sensitivity level the RSTAT flags continue to
indicate the actual receiver state and are only updated if no CSCIF interrupt is pending.
00 Do not generate any CSCIF interrupt caused by receiver state changes.
01 Generate CSCIF interrupt only if the receiver enters or leaves “bus-off” state. Discard other receiver state
changes for generating CSCIF interrupt.
10 Generate CSCIF interrupt only if the receiver enters or leaves “RxErr” or “bus-off”(2) state. Discard other
receiver state changes for generating CSCIF interrupt.
11 Generate CSCIF interrupt on all state changes.
3-2
Transmitter Status Change Enable — These TSTAT enable bits control the sensitivity level in which transmitter
TSTATE[1:0] state changes are causing CSCIF interrupts. Independent of the chosen sensitivity level, the TSTAT flags
continue to indicate the actual transmitter state and are only updated if no CSCIF interrupt is pending.
00 Do not generate any CSCIF interrupt caused by transmitter state changes.
01 Generate CSCIF interrupt only if the transmitter enters or leaves “bus-off” state. Discard other transmitter
state changes for generating CSCIF interrupt.
10 Generate CSCIF interrupt only if the transmitter enters or leaves “TxErr” or “bus-off” state. Discard other
transmitter state changes for generating CSCIF interrupt.
11 Generate CSCIF interrupt on all state changes.
1
OVRIE
Overrun Interrupt Enable
0 No interrupt request is generated from this event.
1 An overrun event causes an error interrupt request.
0
RXFIE
Receiver Full Interrupt Enable
0 No interrupt request is generated from this event.
1 A receive buffer full (successful message reception) event causes a receiver interrupt request.
1. WUPIE and WUPE (see Section 8.3.2.1, “MSCAN Control Register 0 (CANCTL0)”) must both be enabled if the recovery
mechanism from stop or wait is required.
2. Bus-off state is defined by the CAN standard (see Bosch CAN 2.0A/B protocol specification: for only transmitters. Because the
only possible state change for the transmitter from bus-off to TxOK also forces the receiver to skip its current state to RxOK,
the coding of the RXSTAT[1:0] flags define an additional bus-off state for the receiver (see Section 8.3.2.5, “MSCAN Receiver
Flag Register (CANRFLG)”).
8.3.2.7
MSCAN Transmitter Flag Register (CANTFLG)
The transmit buffer empty flags each have an associated interrupt enable bit in the CANTIER register.
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Access: User read/write(1)
Module Base + 0x0006
R
7
6
5
4
3
0
0
0
0
0
2
1
0
TXE2
TXE1
TXE0
1
1
1
W
Reset:
0
0
0
0
0
= Unimplemented
Figure 8-10. MSCAN Transmitter Flag Register (CANTFLG)
1. Read: Anytime
Write: Anytime when not in initialization mode; write of 1 clears flag, write of 0 is ignored
NOTE
The CANTFLG register is held in the reset state when the initialization
mode is active (INITRQ = 1 and INITAK = 1). This register is writable when
not in initialization mode (INITRQ = 0 and INITAK = 0).
Table 8-13. CANTFLG Register Field Descriptions
Field
Description
2-0
TXE[2:0]
Transmitter Buffer Empty — This flag indicates that the associated transmit message buffer is empty, and thus
not scheduled for transmission. The CPU must clear the flag after a message is set up in the transmit buffer and
is due for transmission. The MSCAN sets the flag after the message is sent successfully. The flag is also set by
the MSCAN when the transmission request is successfully aborted due to a pending abort request (see
Section 8.3.2.9, “MSCAN Transmitter Message Abort Request Register (CANTARQ)”). If not masked, a transmit
interrupt is pending while this flag is set.
Clearing a TXEx flag also clears the corresponding ABTAKx (see Section 8.3.2.10, “MSCAN Transmitter
Message Abort Acknowledge Register (CANTAAK)”). When a TXEx flag is set, the corresponding ABTRQx bit
is cleared (see Section 8.3.2.9, “MSCAN Transmitter Message Abort Request Register (CANTARQ)”).
When listen-mode is active (see Section 8.3.2.2, “MSCAN Control Register 1 (CANCTL1)”) the TXEx flags
cannot be cleared and no transmission is started.
Read and write accesses to the transmit buffer will be blocked, if the corresponding TXEx bit is cleared
(TXEx = 0) and the buffer is scheduled for transmission.
0 The associated message buffer is full (loaded with a message due for transmission)
1 The associated message buffer is empty (not scheduled)
8.3.2.8
MSCAN Transmitter Interrupt Enable Register (CANTIER)
This register contains the interrupt enable bits for the transmit buffer empty interrupt flags.
Access: User read/write(1)
Module Base + 0x0007
R
7
6
5
4
3
0
0
0
0
0
2
1
0
TXEIE2
TXEIE1
TXEIE0
0
0
0
W
Reset:
0
0
0
0
0
= Unimplemented
Figure 8-11. MSCAN Transmitter Interrupt Enable Register (CANTIER)
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1. Read: Anytime
Write: Anytime when not in initialization mode
NOTE
The CANTIER register is held in the reset state when the initialization mode
is active (INITRQ = 1 and INITAK = 1). This register is writable when not
in initialization mode (INITRQ = 0 and INITAK = 0).
Table 8-14. CANTIER Register Field Descriptions
Field
Description
2-0
TXEIE[2:0]
8.3.2.9
Transmitter Empty Interrupt Enable
0 No interrupt request is generated from this event.
1 A transmitter empty (transmit buffer available for transmission) event causes a transmitter empty interrupt
request.
MSCAN Transmitter Message Abort Request Register (CANTARQ)
The CANTARQ register allows abort request of queued messages as described below.
Access: User read/write(1)
Module Base + 0x0008
R
7
6
5
4
3
0
0
0
0
0
2
1
0
ABTRQ2
ABTRQ1
ABTRQ0
0
0
0
W
Reset:
0
0
0
0
0
= Unimplemented
Figure 8-12. MSCAN Transmitter Message Abort Request Register (CANTARQ)
1. Read: Anytime
Write: Anytime when not in initialization mode
NOTE
The CANTARQ register is held in the reset state when the initialization
mode is active (INITRQ = 1 and INITAK = 1). This register is writable when
not in initialization mode (INITRQ = 0 and INITAK = 0).
Table 8-15. CANTARQ Register Field Descriptions
Field
Description
2-0
Abort Request — The CPU sets the ABTRQx bit to request that a scheduled message buffer (TXEx = 0) be
ABTRQ[2:0] aborted. The MSCAN grants the request if the message has not already started transmission, or if the
transmission is not successful (lost arbitration or error). When a message is aborted, the associated TXE (see
Section 8.3.2.7, “MSCAN Transmitter Flag Register (CANTFLG)”) and abort acknowledge flags (ABTAK, see
Section 8.3.2.10, “MSCAN Transmitter Message Abort Acknowledge Register (CANTAAK)”) are set and a
transmit interrupt occurs if enabled. The CPU cannot reset ABTRQx. ABTRQx is reset whenever the associated
TXE flag is set.
0 No abort request
1 Abort request pending
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8.3.2.10
MSCAN Transmitter Message Abort Acknowledge Register (CANTAAK)
The CANTAAK register indicates the successful abort of a queued message, if requested by the
appropriate bits in the CANTARQ register.
Access: User read/write(1)
Module Base + 0x0009
R
7
6
5
4
3
2
1
0
0
0
0
0
0
ABTAK2
ABTAK1
ABTAK0
0
0
0
0
0
0
0
0
W
Reset:
= Unimplemented
Figure 8-13. MSCAN Transmitter Message Abort Acknowledge Register (CANTAAK)
1. Read: Anytime
Write: Unimplemented
NOTE
The CANTAAK register is held in the reset state when the initialization
mode is active (INITRQ = 1 and INITAK = 1).
Table 8-16. CANTAAK Register Field Descriptions
Field
Description
2-0
Abort Acknowledge — This flag acknowledges that a message was aborted due to a pending abort request
ABTAK[2:0] from the CPU. After a particular message buffer is flagged empty, this flag can be used by the application
software to identify whether the message was aborted successfully or was sent anyway. The ABTAKx flag is
cleared whenever the corresponding TXE flag is cleared.
0 The message was not aborted.
1 The message was aborted.
8.3.2.11
MSCAN Transmit Buffer Selection Register (CANTBSEL)
The CANTBSEL register allows the selection of the actual transmit message buffer, which then will be
accessible in the CANTXFG register space.
Access: User read/write(1)
Module Base + 0x000A
R
7
6
5
4
3
0
0
0
0
0
2
1
0
TX2
TX1
TX0
0
0
0
W
Reset:
0
0
0
0
0
= Unimplemented
Figure 8-14. MSCAN Transmit Buffer Selection Register (CANTBSEL)
1. Read: Find the lowest ordered bit set to 1, all other bits will be read as 0
Write: Anytime when not in initialization mode
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NOTE
The CANTBSEL register is held in the reset state when the initialization
mode is active (INITRQ = 1 and INITAK=1). This register is writable when
not in initialization mode (INITRQ = 0 and INITAK = 0).
Table 8-17. CANTBSEL Register Field Descriptions
Field
Description
2-0
TX[2:0]
Transmit Buffer Select — The lowest numbered bit places the respective transmit buffer in the CANTXFG
register space (e.g., TX1 = 1 and TX0 = 1 selects transmit buffer TX0; TX1 = 1 and TX0 = 0 selects transmit
buffer TX1). Read and write accesses to the selected transmit buffer will be blocked, if the corresponding TXEx
bit is cleared and the buffer is scheduled for transmission (see Section 8.3.2.7, “MSCAN Transmitter Flag
Register (CANTFLG)”).
0 The associated message buffer is deselected
1 The associated message buffer is selected, if lowest numbered bit
The following gives a short programming example of the usage of the CANTBSEL register:
To get the next available transmit buffer, application software must read the CANTFLG register and write
this value back into the CANTBSEL register. In this example Tx buffers TX1 and TX2 are available. The
value read from CANTFLG is therefore 0b0000_0110. When writing this value back to CANTBSEL, the
Tx buffer TX1 is selected in the CANTXFG because the lowest numbered bit set to 1 is at bit position 1.
Reading back this value out of CANTBSEL results in 0b0000_0010, because only the lowest numbered
bit position set to 1 is presented. This mechanism eases the application software the selection of the next
available Tx buffer.
• LDAA CANTFLG; value read is 0b0000_0110
• STAA CANTBSEL; value written is 0b0000_0110
• LDAA CANTBSEL; value read is 0b0000_0010
If all transmit message buffers are deselected, no accesses are allowed to the CANTXFG registers.
8.3.2.12
MSCAN Identifier Acceptance Control Register (CANIDAC)
The CANIDAC register is used for identifier acceptance control as described below.
Access: User read/write(1)
Module Base + 0x000B
R
7
6
0
0
5
4
IDAM1
IDAM0
0
0
3
2
1
0
0
IDHIT2
IDHIT1
IDHIT0
0
0
0
0
W
Reset:
0
0
= Unimplemented
Figure 8-15. MSCAN Identifier Acceptance Control Register (CANIDAC)
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1), except bits IDHITx, which are read-only
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Table 8-18. CANIDAC Register Field Descriptions
Field
Description
5-4
IDAM[1:0]
Identifier Acceptance Mode — The CPU sets these flags to define the identifier acceptance filter organization
(see Section 8.4.3, “Identifier Acceptance Filter”). Table 8-19 summarizes the different settings. In filter closed
mode, no message is accepted such that the foreground buffer is never reloaded.
2-0
IDHIT[2:0]
Identifier Acceptance Hit Indicator — The MSCAN sets these flags to indicate an identifier acceptance hit (see
Section 8.4.3, “Identifier Acceptance Filter”). Table 8-20 summarizes the different settings.
Table 8-19. Identifier Acceptance Mode Settings
IDAM1
IDAM0
Identifier Acceptance Mode
0
0
Two 32-bit acceptance filters
0
1
Four 16-bit acceptance filters
1
0
Eight 8-bit acceptance filters
1
1
Filter closed
Table 8-20. Identifier Acceptance Hit Indication
IDHIT2
IDHIT1
IDHIT0
Identifier Acceptance Hit
0
0
0
Filter 0 hit
0
0
1
Filter 1 hit
0
1
0
Filter 2 hit
0
1
1
Filter 3 hit
1
0
0
Filter 4 hit
1
0
1
Filter 5 hit
1
1
0
Filter 6 hit
1
1
1
Filter 7 hit
The IDHITx indicators are always related to the message in the foreground buffer (RxFG). When a
message gets shifted into the foreground buffer of the receiver FIFO the indicators are updated as well.
8.3.2.13
MSCAN Reserved Register
This register is reserved for factory testing of the MSCAN module and is not available in normal system
operating modes.
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Access: User read/write(1)
Module Base + 0x000C to Module Base + 0x000D
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset:
= Unimplemented
Figure 8-16. MSCAN Reserved Register
1. Read: Always reads zero in normal system operation modes
Write: Unimplemented in normal system operation modes
NOTE
Writing to this register when in special systm operating modes can alter the
MSCAN functionality.
8.3.2.14
MSCAN Miscellaneous Register (CANMISC)
This register provides additional features.
Access: User read/write(1)
Module Base + 0x000D
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
BOHOLD
W
Reset:
0
0
0
0
0
0
0
0
= Unimplemented
Figure 8-17. MSCAN Miscellaneous Register (CANMISC)
1. Read: Anytime
Write: Anytime; write of ‘1’ clears flag; write of ‘0’ ignored
Table 8-21. CANMISC Register Field Descriptions
Field
Description
0
BOHOLD
Bus-off State Hold Until User Request — If BORM is set in MSCAN Control Register 1 (CANCTL1), this bit
indicates whether the module has entered the bus-off state. Clearing this bit requests the recovery from bus-off.
Refer to Section 8.5.2, “Bus-Off Recovery,” for details.
0 Module is not bus-off or recovery has been requested by user in bus-off state
1 Module is bus-off and holds this state until user request
8.3.2.15
MSCAN Receive Error Counter (CANRXERR)
This register reflects the status of the MSCAN receive error counter.
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Access: User read/write(1)
Module Base + 0x000E
R
7
6
5
4
3
2
1
0
RXERR7
RXERR6
RXERR5
RXERR4
RXERR3
RXERR2
RXERR1
RXERR0
0
0
0
0
0
0
0
0
W
Reset:
= Unimplemented
Figure 8-18. MSCAN Receive Error Counter (CANRXERR)
1. Read: Only when in sleep mode (SLPRQ = 1 and SLPAK = 1) or initialization mode (INITRQ = 1 and INITAK = 1)
Write: Unimplemented
NOTE
Reading this register when in any other mode other than sleep or
initialization mode may return an incorrect value. For MCUs with dual
CPUs, this may result in a CPU fault condition.
Writing to this register when in special modes can alter the MSCAN
functionality.
8.3.2.16
MSCAN Transmit Error Counter (CANTXERR)
This register reflects the status of the MSCAN transmit error counter.
Access: User read/write(1)
Module Base + 0x000F
R
7
6
5
4
3
2
1
0
TXERR7
TXERR6
TXERR5
TXERR4
TXERR3
TXERR2
TXERR1
TXERR0
0
0
0
0
0
0
0
0
W
Reset:
= Unimplemented
Figure 8-19. MSCAN Transmit Error Counter (CANTXERR)
1. Read: Only when in sleep mode (SLPRQ = 1 and SLPAK = 1) or initialization mode (INITRQ = 1 and INITAK = 1)
Write: Unimplemented
NOTE
Reading this register when in any other mode other than sleep or
initialization mode, may return an incorrect value. For MCUs with dual
CPUs, this may result in a CPU fault condition.
Writing to this register when in special modes can alter the MSCAN
functionality.
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8.3.2.17
MSCAN Identifier Acceptance Registers (CANIDAR0-7)
On reception, each message is written into the background receive buffer. The CPU is only signalled to
read the message if it passes the criteria in the identifier acceptance and identifier mask registers
(accepted); otherwise, the message is overwritten by the next message (dropped).
The acceptance registers of the MSCAN are applied on the IDR0–IDR3 registers (see Section 8.3.3.1,
“Identifier Registers (IDR0–IDR3)”) of incoming messages in a bit by bit manner (see Section 8.4.3,
“Identifier Acceptance Filter”).
For extended identifiers, all four acceptance and mask registers are applied. For standard identifiers, only
the first two (CANIDAR0/1, CANIDMR0/1) are applied.
Access: User read/write(1)
Module Base + 0x0010 to Module Base + 0x0013
7
6
5
4
3
2
1
0
AC7
AC6
AC5
AC4
AC3
AC2
AC1
AC0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 8-20. MSCAN Identifier Acceptance Registers (First Bank) — CANIDAR0–CANIDAR3
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
Table 8-22. CANIDAR0–CANIDAR3 Register Field Descriptions
Field
Description
7-0
AC[7:0]
Acceptance Code Bits — AC[7:0] comprise a user-defined sequence of bits with which the corresponding bits
of the related identifier register (IDRn) of the receive message buffer are compared. The result of this comparison
is then masked with the corresponding identifier mask register.
Access: User read/write(1)
Module Base + 0x0018 to Module Base + 0x001B
7
6
5
4
3
2
1
0
AC7
AC6
AC5
AC4
AC3
AC2
AC1
AC0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 8-21. MSCAN Identifier Acceptance Registers (Second Bank) — CANIDAR4–CANIDAR7
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
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Table 8-23. CANIDAR4–CANIDAR7 Register Field Descriptions
Field
Description
7-0
AC[7:0]
Acceptance Code Bits — AC[7:0] comprise a user-defined sequence of bits with which the corresponding bits
of the related identifier register (IDRn) of the receive message buffer are compared. The result of this comparison
is then masked with the corresponding identifier mask register.
8.3.2.18
MSCAN Identifier Mask Registers (CANIDMR0–CANIDMR7)
The identifier mask register specifies which of the corresponding bits in the identifier acceptance register
are relevant for acceptance filtering. To receive standard identifiers in 32 bit filter mode, it is required to
program the last three bits (AM[2:0]) in the mask registers CANIDMR1 and CANIDMR5 to “don’t care.”
To receive standard identifiers in 16 bit filter mode, it is required to program the last three bits (AM[2:0])
in the mask registers CANIDMR1, CANIDMR3, CANIDMR5, and CANIDMR7 to “don’t care.”
Access: User read/write(1)
Module Base + 0x0014 to Module Base + 0x0017
7
6
5
4
3
2
1
0
AM7
AM6
AM5
AM4
AM3
AM2
AM1
AM0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 8-22. MSCAN Identifier Mask Registers (First Bank) — CANIDMR0–CANIDMR3
1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
Table 8-24. CANIDMR0–CANIDMR3 Register Field Descriptions
Field
Description
7-0
AM[7:0]
Acceptance Mask Bits — If a particular bit in this register is cleared, this indicates that the corresponding bit in
the identifier acceptance register must be the same as its identifier bit before a match is detected. The message
is accepted if all such bits match. If a bit is set, it indicates that the state of the corresponding bit in the identifier
acceptance register does not affect whether or not the message is accepted.
0 Match corresponding acceptance code register and identifier bits
1 Ignore corresponding acceptance code register bit
Access: User read/write(1)
Module Base + 0x001C to Module Base + 0x001F
7
6
5
4
3
2
1
0
AM7
AM6
AM5
AM4
AM3
AM2
AM1
AM0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 8-23. MSCAN Identifier Mask Registers (Second Bank) — CANIDMR4–CANIDMR7
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1. Read: Anytime
Write: Anytime in initialization mode (INITRQ = 1 and INITAK = 1)
Table 8-25. CANIDMR4–CANIDMR7 Register Field Descriptions
Field
Description
7-0
AM[7:0]
Acceptance Mask Bits — If a particular bit in this register is cleared, this indicates that the corresponding bit in
the identifier acceptance register must be the same as its identifier bit before a match is detected. The message
is accepted if all such bits match. If a bit is set, it indicates that the state of the corresponding bit in the identifier
acceptance register does not affect whether or not the message is accepted.
0 Match corresponding acceptance code register and identifier bits
1 Ignore corresponding acceptance code register bit
8.3.3
Programmer’s Model of Message Storage
The following section details the organization of the receive and transmit message buffers and the
associated control registers.
To simplify the programmer interface, the receive and transmit message buffers have the same outline.
Each message buffer allocates 16 bytes in the memory map containing a 13 byte data structure.
An additional transmit buffer priority register (TBPR) is defined for the transmit buffers. Within the last
two bytes of this memory map, the MSCAN stores a special 16-bit time stamp, which is sampled from an
internal timer after successful transmission or reception of a message. This feature is only available for
transmit and receiver buffers, if the TIME bit is set (see Section 8.3.2.1, “MSCAN Control Register 0
(CANCTL0)”).
The time stamp register is written by the MSCAN. The CPU can only read these registers.
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Table 8-26. Message Buffer Organization
Offset
Address
Register
Access
0x00X0
Identifier Register 0
R/W
0x00X1
Identifier Register 1
R/W
0x00X2
Identifier Register 2
R/W
0x00X3
Identifier Register 3
R/W
0x00X4
Data Segment Register 0
R/W
0x00X5
Data Segment Register 1
R/W
0x00X6
Data Segment Register 2
R/W
0x00X7
Data Segment Register 3
R/W
0x00X8
Data Segment Register 4
R/W
0x00X9
Data Segment Register 5
R/W
0x00XA
Data Segment Register 6
R/W
0x00XB
Data Segment Register 7
R/W
0x00XC
Data Length Register
R/W
(1)
0x00XD
Transmit Buffer Priority Register
R/W
0x00XE
Time Stamp Register (High Byte)
R
0x00XF
Time Stamp Register (Low Byte)
1. Not applicable for receive buffers
R
Figure 8-24 shows the common 13-byte data structure of receive and transmit buffers for extended
identifiers. The mapping of standard identifiers into the IDR registers is shown in Figure 8-25.
All bits of the receive and transmit buffers are ‘x’ out of reset because of RAM-based implementation1.
All reserved or unused bits of the receive and transmit buffers always read ‘x’.
Figure 8-24. Receive/Transmit Message Buffer — Extended Identifier Mapping
Register
Name
0x00X0
IDR0
0x00X1
IDR1
0x00X2
IDR2
0x00X3
IDR3
Bit 7
6
5
4
3
2
1
Bit0
ID28
ID27
ID26
ID25
ID24
ID23
ID22
ID21
ID20
ID19
ID18
SRR (=1)
IDE (=1)
ID17
ID16
ID15
ID14
ID13
ID12
ID11
ID10
ID9
ID8
ID7
ID6
ID5
ID4
ID3
ID2
ID1
ID0
RTR
R
W
R
W
R
W
R
W
1. Exception: The transmit buffer priority registers are 0 out of reset.
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Figure 8-24. Receive/Transmit Message Buffer — Extended Identifier Mapping (continued)
Register
Name
0x00X4
DSR0
0x00X5
DSR1
0x00X6
DSR2
0x00X7
DSR3
0x00X8
DSR4
0x00X9
DSR5
0x00XA
DSR6
0x00XB
DSR7
0x00XC
DLR
Bit 7
6
5
4
3
2
1
Bit0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DLC3
DLC2
DLC1
DLC0
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
= Unused, always read ‘x’
Read:
• For transmit buffers, anytime when TXEx flag is set (see Section 8.3.2.7, “MSCAN Transmitter
Flag Register (CANTFLG)”) and the corresponding transmit buffer is selected in CANTBSEL (see
Section 8.3.2.11, “MSCAN Transmit Buffer Selection Register (CANTBSEL)”).
• For receive buffers, only when RXF flag is set (see Section 8.3.2.5, “MSCAN Receiver Flag
Register (CANRFLG)”).
Write:
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•
•
For transmit buffers, anytime when TXEx flag is set (see Section 8.3.2.7, “MSCAN Transmitter
Flag Register (CANTFLG)”) and the corresponding transmit buffer is selected in CANTBSEL (see
Section 8.3.2.11, “MSCAN Transmit Buffer Selection Register (CANTBSEL)”).
Unimplemented for receive buffers.
Reset: Undefined because of RAM-based implementation
Figure 8-25. Receive/Transmit Message Buffer — Standard Identifier Mapping
Register
Name
IDR0
0x00X0
IDR1
0x00X1
IDR2
0x00X2
IDR3
0x00X3
Bit 7
6
5
4
3
2
1
Bit 0
ID10
ID9
ID8
ID7
ID6
ID5
ID4
ID3
ID2
ID1
ID0
RTR
IDE (=0)
R
W
R
W
R
W
R
W
= Unused, always read ‘x’
8.3.3.1
Identifier Registers (IDR0–IDR3)
The identifier registers for an extended format identifier consist of a total of 32 bits; ID[28:0], SRR, IDE,
and RTR bits. The identifier registers for a standard format identifier consist of a total of 13 bits; ID[10:0],
RTR, and IDE bits.
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8.3.3.1.1
IDR0–IDR3 for Extended Identifier Mapping
Module Base + 0x00X0
7
6
5
4
3
2
1
0
ID28
ID27
ID26
ID25
ID24
ID23
ID22
ID21
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 8-26. Identifier Register 0 (IDR0) — Extended Identifier Mapping
Table 8-27. IDR0 Register Field Descriptions — Extended
Field
Description
7-0
ID[28:21]
Extended Format Identifier — The identifiers consist of 29 bits (ID[28:0]) for the extended format. ID28 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number.
Module Base + 0x00X1
7
6
5
4
3
2
1
0
ID20
ID19
ID18
SRR (=1)
IDE (=1)
ID17
ID16
ID15
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 8-27. Identifier Register 1 (IDR1) — Extended Identifier Mapping
Table 8-28. IDR1 Register Field Descriptions — Extended
Field
Description
7-5
ID[20:18]
Extended Format Identifier — The identifiers consist of 29 bits (ID[28:0]) for the extended format. ID28 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number.
4
SRR
Substitute Remote Request — This fixed recessive bit is used only in extended format. It must be set to 1 by
the user for transmission buffers and is stored as received on the CAN bus for receive buffers.
3
IDE
ID Extended — This flag indicates whether the extended or standard identifier format is applied in this buffer. In
the case of a receive buffer, the flag is set as received and indicates to the CPU how to process the buffer
identifier registers. In the case of a transmit buffer, the flag indicates to the MSCAN what type of identifier to send.
0 Standard format (11 bit)
1 Extended format (29 bit)
2-0
ID[17:15]
Extended Format Identifier — The identifiers consist of 29 bits (ID[28:0]) for the extended format. ID28 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number.
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Module Base + 0x00X2
7
6
5
4
3
2
1
0
ID14
ID13
ID12
ID11
ID10
ID9
ID8
ID7
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 8-28. Identifier Register 2 (IDR2) — Extended Identifier Mapping
Table 8-29. IDR2 Register Field Descriptions — Extended
Field
Description
7-0
ID[14:7]
Extended Format Identifier — The identifiers consist of 29 bits (ID[28:0]) for the extended format. ID28 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number.
Module Base + 0x00X3
7
6
5
4
3
2
1
0
ID6
ID5
ID4
ID3
ID2
ID1
ID0
RTR
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 8-29. Identifier Register 3 (IDR3) — Extended Identifier Mapping
Table 8-30. IDR3 Register Field Descriptions — Extended
Field
Description
7-1
ID[6:0]
Extended Format Identifier — The identifiers consist of 29 bits (ID[28:0]) for the extended format. ID28 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number.
0
RTR
Remote Transmission Request — This flag reflects the status of the remote transmission request bit in the
CAN frame. In the case of a receive buffer, it indicates the status of the received frame and supports the
transmission of an answering frame in software. In the case of a transmit buffer, this flag defines the setting of
the RTR bit to be sent.
0 Data frame
1 Remote frame
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8.3.3.1.2
IDR0–IDR3 for Standard Identifier Mapping
Module Base + 0x00X0
7
6
5
4
3
2
1
0
ID10
ID9
ID8
ID7
ID6
ID5
ID4
ID3
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 8-30. Identifier Register 0 — Standard Mapping
Table 8-31. IDR0 Register Field Descriptions — Standard
Field
Description
7-0
ID[10:3]
Standard Format Identifier — The identifiers consist of 11 bits (ID[10:0]) for the standard format. ID10 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number. See also ID bits in Table 8-32.
Module Base + 0x00X1
7
6
5
4
3
ID2
ID1
ID0
RTR
IDE (=0)
x
x
x
x
x
2
1
0
x
x
x
R
W
Reset:
= Unused; always read ‘x’
Figure 8-31. Identifier Register 1 — Standard Mapping
Table 8-32. IDR1 Register Field Descriptions
Field
Description
7-5
ID[2:0]
Standard Format Identifier — The identifiers consist of 11 bits (ID[10:0]) for the standard format. ID10 is the
most significant bit and is transmitted first on the CAN bus during the arbitration procedure. The priority of an
identifier is defined to be highest for the smallest binary number. See also ID bits in Table 8-31.
4
RTR
Remote Transmission Request — This flag reflects the status of the Remote Transmission Request bit in the
CAN frame. In the case of a receive buffer, it indicates the status of the received frame and supports the
transmission of an answering frame in software. In the case of a transmit buffer, this flag defines the setting of
the RTR bit to be sent.
0 Data frame
1 Remote frame
3
IDE
ID Extended — This flag indicates whether the extended or standard identifier format is applied in this buffer. In
the case of a receive buffer, the flag is set as received and indicates to the CPU how to process the buffer
identifier registers. In the case of a transmit buffer, the flag indicates to the MSCAN what type of identifier to send.
0 Standard format (11 bit)
1 Extended format (29 bit)
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Module Base + 0x00X2
7
6
5
4
3
2
1
0
x
x
x
x
x
x
x
x
R
W
Reset:
= Unused; always read ‘x’
Figure 8-32. Identifier Register 2 — Standard Mapping
Module Base + 0x00X3
7
6
5
4
3
2
1
0
x
x
x
x
x
x
x
x
R
W
Reset:
= Unused; always read ‘x’
Figure 8-33. Identifier Register 3 — Standard Mapping
8.3.3.2
Data Segment Registers (DSR0-7)
The eight data segment registers, each with bits DB[7:0], contain the data to be transmitted or received.
The number of bytes to be transmitted or received is determined by the data length code in the
corresponding DLR register.
Module Base + 0x00X4 to Module Base + 0x00XB
7
6
5
4
3
2
1
0
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
x
x
x
x
x
x
x
x
R
W
Reset:
Figure 8-34. Data Segment Registers (DSR0–DSR7) — Extended Identifier Mapping
Table 8-33. DSR0–DSR7 Register Field Descriptions
Field
7-0
DB[7:0]
Description
Data bits 7-0
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8.3.3.3
Data Length Register (DLR)
This register keeps the data length field of the CAN frame.
Module Base + 0x00XC
7
6
5
4
3
2
1
0
DLC3
DLC2
DLC1
DLC0
x
x
x
x
R
W
Reset:
x
x
x
x
= Unused; always read “x”
Figure 8-35. Data Length Register (DLR) — Extended Identifier Mapping
Table 8-34. DLR Register Field Descriptions
Field
Description
3-0
DLC[3:0]
Data Length Code Bits — The data length code contains the number of bytes (data byte count) of the respective
message. During the transmission of a remote frame, the data length code is transmitted as programmed while
the number of transmitted data bytes is always 0. The data byte count ranges from 0 to 8 for a data frame.
Table 8-35 shows the effect of setting the DLC bits.
Table 8-35. Data Length Codes
Data Length Code
8.3.3.4
DLC3
DLC2
DLC1
DLC0
Data Byte
Count
0
0
0
0
0
0
0
0
1
1
0
0
1
0
2
0
0
1
1
3
0
1
0
0
4
0
1
0
1
5
0
1
1
0
6
0
1
1
1
7
1
0
0
0
8
Transmit Buffer Priority Register (TBPR)
This register defines the local priority of the associated message buffer. The local priority is used for the
internal prioritization process of the MSCAN and is defined to be highest for the smallest binary number.
The MSCAN implements the following internal prioritization mechanisms:
• All transmission buffers with a cleared TXEx flag participate in the prioritization immediately
before the SOF (start of frame) is sent.
• The transmission buffer with the lowest local priority field wins the prioritization.
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In cases of more than one buffer having the same lowest priority, the message buffer with the lower index
number wins.
Access: User read/write(1)
Module Base + 0x00XD
7
6
5
4
3
2
1
0
PRIO7
PRIO6
PRIO5
PRIO4
PRIO3
PRIO2
PRIO1
PRIO0
0
0
0
0
0
0
0
0
R
W
Reset:
Figure 8-36. Transmit Buffer Priority Register (TBPR)
1. Read: Anytime when TXEx flag is set (see Section 8.3.2.7, “MSCAN Transmitter Flag Register (CANTFLG)”) and the
corresponding transmit buffer is selected in CANTBSEL (see Section 8.3.2.11, “MSCAN Transmit Buffer Selection Register
(CANTBSEL)”)
Write: Anytime when TXEx flag is set (see Section 8.3.2.7, “MSCAN Transmitter Flag Register (CANTFLG)”) and the
corresponding transmit buffer is selected in CANTBSEL (see Section 8.3.2.11, “MSCAN Transmit Buffer Selection Register
(CANTBSEL)”)
8.3.3.5
Time Stamp Register (TSRH–TSRL)
If the TIME bit is enabled, the MSCAN will write a time stamp to the respective registers in the active
transmit or receive buffer right after the EOF of a valid message on the CAN bus (see Section 8.3.2.1,
“MSCAN Control Register 0 (CANCTL0)”). In case of a transmission, the CPU can only read the time
stamp after the respective transmit buffer has been flagged empty.
The timer value, which is used for stamping, is taken from a free running internal CAN bit clock. A timer
overrun is not indicated by the MSCAN. The timer is reset (all bits set to 0) during initialization mode. The
CPU can only read the time stamp registers.
Access: User read/write(1)
Module Base + 0x00XE
R
7
6
5
4
3
2
1
0
TSR15
TSR14
TSR13
TSR12
TSR11
TSR10
TSR9
TSR8
x
x
x
x
x
x
x
x
W
Reset:
Figure 8-37. Time Stamp Register — High Byte (TSRH)
1. Read: Anytime when TXEx flag is set (see Section 8.3.2.7, “MSCAN Transmitter Flag Register (CANTFLG)”) and the
corresponding transmit buffer is selected in CANTBSEL (see Section 8.3.2.11, “MSCAN Transmit Buffer Selection Register
(CANTBSEL)”)
Write: Unimplemented
Access: User read/write(1)
Module Base + 0x00XF
R
7
6
5
4
3
2
1
0
TSR7
TSR6
TSR5
TSR4
TSR3
TSR2
TSR1
TSR0
x
x
x
x
x
x
x
x
W
Reset:
Figure 8-38. Time Stamp Register — Low Byte (TSRL)
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1. Read: Anytime when TXEx flag is set (see Section 8.3.2.7, “MSCAN Transmitter Flag Register (CANTFLG)”) and the
corresponding transmit buffer is selected in CANTBSEL (see Section 8.3.2.11, “MSCAN Transmit Buffer Selection Register
(CANTBSEL)”)
Write: Unimplemented
8.4
8.4.1
Functional Description
General
This section provides a complete functional description of the MSCAN.
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8.4.2
Message Storage
CAN Receive / Transmit Engine
Memory Mapped I/O
Rx0
RXF
CPU bus
RxFG
RxBG
MSCAN
Rx1
Rx2
Rx3
Rx4
Receiver
TxBG
Tx0
MSCAN
TxFG
Tx1
Transmitter
TxBG
Tx2
TXE0
PRIO
TXE1
CPU bus
PRIO
TXE2
PRIO
Figure 8-39. User Model for Message Buffer Organization
The MSCAN facilitates a sophisticated message storage system which addresses the requirements of a
broad range of network applications.
8.4.2.1
Message Transmit Background
Modern application layer software is built upon two fundamental assumptions:
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•
•
Any CAN node is able to send out a stream of scheduled messages without releasing the CAN bus
between the two messages. Such nodes arbitrate for the CAN bus immediately after sending the
previous message and only release the CAN bus in case of lost arbitration.
The internal message queue within any CAN node is organized such that the highest priority
message is sent out first, if more than one message is ready to be sent.
The behavior described in the bullets above cannot be achieved with a single transmit buffer. That buffer
must be reloaded immediately after the previous message is sent. This loading process lasts a finite amount
of time and must be completed within the inter-frame sequence (IFS) to be able to send an uninterrupted
stream of messages. Even if this is feasible for limited CAN bus speeds, it requires that the CPU reacts
with short latencies to the transmit interrupt.
A double buffer scheme de-couples the reloading of the transmit buffer from the actual message sending
and, therefore, reduces the reactiveness requirements of the CPU. Problems can arise if the sending of a
message is finished while the CPU re-loads the second buffer. No buffer would then be ready for
transmission, and the CAN bus would be released.
At least three transmit buffers are required to meet the first of the above requirements under all
circumstances. The MSCAN has three transmit buffers.
The second requirement calls for some sort of internal prioritization which the MSCAN implements with
the “local priority” concept described in Section 8.4.2.2, “Transmit Structures.”
8.4.2.2
Transmit Structures
The MSCAN triple transmit buffer scheme optimizes real-time performance by allowing multiple
messages to be set up in advance. The three buffers are arranged as shown in Figure 8-39.
All three buffers have a 13-byte data structure similar to the outline of the receive buffers (see
Section 8.3.3, “Programmer’s Model of Message Storage”). An additional Transmit Buffer Priority
Register (TBPR) contains an 8-bit local priority field (PRIO) (see Section 8.3.3.4, “Transmit Buffer
Priority Register (TBPR)”). The remaining two bytes are used for time stamping of a message, if required
(see Section 8.3.3.5, “Time Stamp Register (TSRH–TSRL)”).
To transmit a message, the CPU must identify an available transmit buffer, which is indicated by a set
transmitter buffer empty (TXEx) flag (see Section 8.3.2.7, “MSCAN Transmitter Flag Register
(CANTFLG)”). If a transmit buffer is available, the CPU must set a pointer to this buffer by writing to the
CANTBSEL register (see Section 8.3.2.11, “MSCAN Transmit Buffer Selection Register
(CANTBSEL)”). This makes the respective buffer accessible within the CANTXFG address space (see
Section 8.3.3, “Programmer’s Model of Message Storage”). The algorithmic feature associated with the
CANTBSEL register simplifies the transmit buffer selection. In addition, this scheme makes the handler
software simpler because only one address area is applicable for the transmit process, and the required
address space is minimized.
The CPU then stores the identifier, the control bits, and the data content into one of the transmit buffers.
Finally, the buffer is flagged as ready for transmission by clearing the associated TXE flag.
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The MSCAN then schedules the message for transmission and signals the successful transmission of the
buffer by setting the associated TXE flag. A transmit interrupt (see Section 8.4.7.2, “Transmit Interrupt”)
is generated1 when TXEx is set and can be used to drive the application software to re-load the buffer.
If more than one buffer is scheduled for transmission when the CAN bus becomes available for arbitration,
the MSCAN uses the local priority setting of the three buffers to determine the prioritization. For this
purpose, every transmit buffer has an 8-bit local priority field (PRIO). The application software programs
this field when the message is set up. The local priority reflects the priority of this particular message
relative to the set of messages being transmitted from this node. The lowest binary value of the PRIO field
is defined to be the highest priority. The internal scheduling process takes place whenever the MSCAN
arbitrates for the CAN bus. This is also the case after the occurrence of a transmission error.
When a high priority message is scheduled by the application software, it may become necessary to abort
a lower priority message in one of the three transmit buffers. Because messages that are already in
transmission cannot be aborted, the user must request the abort by setting the corresponding abort request
bit (ABTRQ) (see Section 8.3.2.9, “MSCAN Transmitter Message Abort Request Register
(CANTARQ)”.) The MSCAN then grants the request, if possible, by:
1. Setting the corresponding abort acknowledge flag (ABTAK) in the CANTAAK register.
2. Setting the associated TXE flag to release the buffer.
3. Generating a transmit interrupt. The transmit interrupt handler software can determine from the
setting of the ABTAK flag whether the message was aborted (ABTAK = 1) or sent (ABTAK = 0).
8.4.2.3
Receive Structures
The received messages are stored in a five stage input FIFO. The five message buffers are alternately
mapped into a single memory area (see Figure 8-39). The background receive buffer (RxBG) is exclusively
associated with the MSCAN, but the foreground receive buffer (RxFG) is addressable by the CPU (see
Figure 8-39). This scheme simplifies the handler software because only one address area is applicable for
the receive process.
All receive buffers have a size of 15 bytes to store the CAN control bits, the identifier (standard or
extended), the data contents, and a time stamp, if enabled (see Section 8.3.3, “Programmer’s Model of
Message Storage”).
The receiver full flag (RXF) (see Section 8.3.2.5, “MSCAN Receiver Flag Register (CANRFLG)”) signals
the status of the foreground receive buffer. When the buffer contains a correctly received message with a
matching identifier, this flag is set.
On reception, each message is checked to see whether it passes the filter (see Section 8.4.3, “Identifier
Acceptance Filter”) and simultaneously is written into the active RxBG. After successful reception of a
valid message, the MSCAN shifts the content of RxBG into the receiver FIFO2, sets the RXF flag, and
generates a receive interrupt (see Section 8.4.7.3, “Receive Interrupt”) to the CPU3. The user’s receive
handler must read the received message from the RxFG and then reset the RXF flag to acknowledge the
interrupt and to release the foreground buffer. A new message, which can follow immediately after the IFS
field of the CAN frame, is received into the next available RxBG. If the MSCAN receives an invalid
1. The transmit interrupt occurs only if not masked. A polling scheme can be applied on TXEx also.
2. Only if the RXF flag is not set.
3. The receive interrupt occurs only if not masked. A polling scheme can be applied on RXF also.
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message in its RxBG (wrong identifier, transmission errors, etc.) the actual contents of the buffer will be
over-written by the next message. The buffer will then not be shifted into the FIFO.
When the MSCAN module is transmitting, the MSCAN receives its own transmitted messages into the
background receive buffer, RxBG, but does not shift it into the receiver FIFO, generate a receive interrupt,
or acknowledge its own messages on the CAN bus. The exception to this rule is in loopback mode (see
Section 8.3.2.2, “MSCAN Control Register 1 (CANCTL1)”) where the MSCAN treats its own messages
exactly like all other incoming messages. The MSCAN receives its own transmitted messages in the event
that it loses arbitration. If arbitration is lost, the MSCAN must be prepared to become a receiver.
An overrun condition occurs when all receive message buffers in the FIFO are filled with correctly
received messages with accepted identifiers and another message is correctly received from the CAN bus
with an accepted identifier. The latter message is discarded and an error interrupt with overrun indication
is generated if enabled (see Section 8.4.7.5, “Error Interrupt”). The MSCAN remains able to transmit
messages while the receiver FIFO being filled, but all incoming messages are discarded. As soon as a
receive buffer in the FIFO is available again, new valid messages will be accepted.
8.4.3
Identifier Acceptance Filter
The MSCAN identifier acceptance registers (see Section 8.3.2.12, “MSCAN Identifier Acceptance
Control Register (CANIDAC)”) define the acceptable patterns of the standard or extended identifier
(ID[10:0] or ID[28:0]). Any of these bits can be marked ‘don’t care’ in the MSCAN identifier mask
registers (see Section 8.3.2.18, “MSCAN Identifier Mask Registers (CANIDMR0–CANIDMR7)”).
A filter hit is indicated to the application software by a set receive buffer full flag (RXF = 1) and three bits
in the CANIDAC register (see Section 8.3.2.12, “MSCAN Identifier Acceptance Control Register
(CANIDAC)”). These identifier hit flags (IDHIT[2:0]) clearly identify the filter section that caused the
acceptance. They simplify the application software’s task to identify the cause of the receiver interrupt. If
more than one hit occurs (two or more filters match), the lower hit has priority.
A very flexible programmable generic identifier acceptance filter has been introduced to reduce the CPU
interrupt loading. The filter is programmable to operate in four different modes (see Bosch CAN 2.0A/B
protocol specification):
• Two identifier acceptance filters, each to be applied to:
— The full 29 bits of the extended identifier and to the following bits of the CAN 2.0B frame:
– Remote transmission request (RTR)
– Identifier extension (IDE)
– Substitute remote request (SRR)
— The 11 bits of the standard identifier plus the RTR and IDE bits of the CAN 2.0A/B messages1.
This mode implements two filters for a full length CAN 2.0B compliant extended identifier.
Figure 8-40 shows how the first 32-bit filter bank (CANIDAR0–CANIDAR3,
CANIDMR0–CANIDMR3) produces a filter 0 hit. Similarly, the second filter bank
(CANIDAR4–CANIDAR7, CANIDMR4–CANIDMR7) produces a filter 1 hit.
• Four identifier acceptance filters, each to be applied to
1. Although this mode can be used for standard identifiers, it is recommended to use the four or eight identifier acceptance
filters for standard identifiers
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•
•
— a) the 14 most significant bits of the extended identifier plus the SRR and IDE bits of CAN 2.0B
messages or
— b) the 11 bits of the standard identifier, the RTR and IDE bits of CAN 2.0A/B messages.
Figure 8-41 shows how the first 32-bit filter bank (CANIDAR0–CANIDA3,
CANIDMR0–3CANIDMR) produces filter 0 and 1 hits. Similarly, the second filter bank
(CANIDAR4–CANIDAR7, CANIDMR4–CANIDMR7) produces filter 2 and 3 hits.
Eight identifier acceptance filters, each to be applied to the first 8 bits of the identifier. This mode
implements eight independent filters for the first 8 bits of a CAN 2.0A/B compliant standard
identifier or a CAN 2.0B compliant extended identifier. Figure 8-42 shows how the first 32-bit filter
bank (CANIDAR0–CANIDAR3, CANIDMR0–CANIDMR3) produces filter 0 to 3 hits. Similarly,
the second filter bank (CANIDAR4–CANIDAR7, CANIDMR4–CANIDMR7) produces filter 4 to
7 hits.
Closed filter. No CAN message is copied into the foreground buffer RxFG, and the RXF flag is
never set.
CAN 2.0B
Extended Identifier ID28
IDR0
ID21
ID20
IDR1
CAN 2.0A/B
Standard Identifier ID10
IDR0
ID3
ID2
IDR1
ID15
IDE
ID14
IDR2
ID7
ID6
IDR3
RTR
ID10
IDR2
ID3
ID10
IDR3
ID3
AM7
CANIDMR0
AM0
AM7
CANIDMR1
AM0
AM7
CANIDMR2
AM0
AM7
CANIDMR3
AM0
AC7
CANIDAR0
AC0
AC7
CANIDAR1
AC0
AC7
CANIDAR2
AC0
AC7
CANIDAR3
AC0
ID Accepted (Filter 0 Hit)
Figure 8-40. 32-bit Maskable Identifier Acceptance Filter
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CAN 2.0B
Extended Identifier
ID28
IDR0
ID21
ID20
IDR1
CAN 2.0A/B
Standard Identifier
ID10
IDR0
ID3
ID2
IDR1
AM7
CANIDMR0
AM0
AM7
CANIDMR1
AM0
AC7
CANIDAR0
AC0
AC7
CANIDAR1
AC0
ID15
IDE
ID14
IDR2
ID7
ID6
IDR3
RTR
ID10
IDR2
ID3
ID10
IDR3
ID3
ID Accepted (Filter 0 Hit)
AM7
CANIDMR2
AM0
AM7
CANIDMR3
AM0
AC7
CANIDAR2
AC0
AC7
CANIDAR3
AC0
ID Accepted (Filter 1 Hit)
Figure 8-41. 16-bit Maskable Identifier Acceptance Filters
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CAN 2.0B
Extended Identifier ID28
IDR0
ID21
ID20
IDR1
CAN 2.0A/B
Standard Identifier ID10
IDR0
ID3
ID2
IDR1
AM7
CIDMR0
AM0
AC7
CIDAR0
AC0
ID15
IDE
ID14
IDR2
ID7
ID6
IDR3
RTR
ID10
IDR2
ID3
ID10
IDR3
ID3
ID Accepted (Filter 0 Hit)
AM7
CIDMR1
AM0
AC7
CIDAR1
AC0
ID Accepted (Filter 1 Hit)
AM7
CIDMR2
AM0
AC7
CIDAR2
AC0
ID Accepted (Filter 2 Hit)
AM7
CIDMR3
AM0
AC7
CIDAR3
AC0
ID Accepted (Filter 3 Hit)
Figure 8-42. 8-bit Maskable Identifier Acceptance Filters
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8.4.3.1
Protocol Violation Protection
The MSCAN protects the user from accidentally violating the CAN protocol through programming errors.
The protection logic implements the following features:
• The receive and transmit error counters cannot be written or otherwise manipulated.
• All registers which control the configuration of the MSCAN cannot be modified while the MSCAN
is on-line. The MSCAN has to be in Initialization Mode. The corresponding INITRQ/INITAK
handshake bits in the CANCTL0/CANCTL1 registers (see Section 8.3.2.1, “MSCAN Control
Register 0 (CANCTL0)”) serve as a lock to protect the following registers:
— MSCAN control 1 register (CANCTL1)
— MSCAN bus timing registers 0 and 1 (CANBTR0, CANBTR1)
— MSCAN identifier acceptance control register (CANIDAC)
— MSCAN identifier acceptance registers (CANIDAR0–CANIDAR7)
— MSCAN identifier mask registers (CANIDMR0–CANIDMR7)
• The TXCAN is immediately forced to a recessive state when the MSCAN goes into the power
down mode or initialization mode (see Section 8.4.5.6, “MSCAN Power Down Mode,” and
Section 8.4.4.5, “MSCAN Initialization Mode”).
• The MSCAN enable bit (CANE) is writable only once in normal system operation modes, which
provides further protection against inadvertently disabling the MSCAN.
8.4.3.2
Clock System
Figure 8-43 shows the structure of the MSCAN clock generation circuitry.
MSCAN
Bus Clock
CANCLK
CLKSRC
Prescaler
(1 .. 64)
Time quanta clock (Tq)
CLKSRC
Oscillator Clock
Figure 8-43. MSCAN Clocking Scheme
The clock source bit (CLKSRC) in the CANCTL1 register (8.3.2.2/8-259) defines whether the internal
CANCLK is connected to the output of a crystal oscillator (oscillator clock) or to the bus clock.
The clock source has to be chosen such that the tight oscillator tolerance requirements (up to 0.4%) of the
CAN protocol are met. Additionally, for high CAN bus rates (1 Mbps), a 45% to 55% duty cycle of the
clock is required.
If the bus clock is generated from a PLL, it is recommended to select the oscillator clock rather than the
bus clock due to jitter considerations, especially at the faster CAN bus rates.
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For microcontrollers without a clock and reset generator (CRG), CANCLK is driven from the crystal
oscillator (oscillator clock).
A programmable prescaler generates the time quanta (Tq) clock from CANCLK. A time quantum is the
atomic unit of time handled by the MSCAN.
Eqn. 8-2
f CANCLK
=
----------------------------------------------------Tq ( Prescaler value )A bit time is subdivided into three segments as described in the Bosch CAN specification. (see Figure 844):
• SYNC_SEG: This segment has a fixed length of one time quantum. Signal edges are expected to
happen within this section.
• Time Segment 1: This segment includes the PROP_SEG and the PHASE_SEG1 of the CAN
standard. It can be programmed by setting the parameter TSEG1 to consist of 4 to 16 time quanta.
• Time Segment 2: This segment represents the PHASE_SEG2 of the CAN standard. It can be
programmed by setting the TSEG2 parameter to be 2 to 8 time quanta long.
Eqn. 8-3
f Tq
Bit Rate = --------------------------------------------------------------------------------( number of Time Quanta )
NRZ Signal
SYNC_SEG
Time Segment 1
(PROP_SEG + PHASE_SEG1)
Time Segment 2
(PHASE_SEG2)
1
4 ... 16
2 ... 8
8 ... 25 Time Quanta
= 1 Bit Time
Transmit Point
Sample Point
(single or triple sampling)
Figure 8-44. Segments within the Bit Time
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Table 8-36. Time Segment Syntax
Syntax
Description
System expects transitions to occur on the CAN bus during this
period.
SYNC_SEG
Transmit Point
A node in transmit mode transfers a new value to the CAN bus at
this point.
Sample Point
A node in receive mode samples the CAN bus at this point. If the
three samples per bit option is selected, then this point marks the
position of the third sample.
The synchronization jump width (see the Bosch CAN specification for details) can be programmed in a
range of 1 to 4 time quanta by setting the SJW parameter.
The SYNC_SEG, TSEG1, TSEG2, and SJW parameters are set by programming the MSCAN bus timing
registers (CANBTR0, CANBTR1) (see Section 8.3.2.3, “MSCAN Bus Timing Register 0 (CANBTR0)”
and Section 8.3.2.4, “MSCAN Bus Timing Register 1 (CANBTR1)”).
Table 8-37 gives an overview of the CAN compliant segment settings and the related parameter values.
NOTE
It is the user’s responsibility to ensure the bit time settings are in compliance
with the CAN standard.
Table 8-37. CAN Standard Compliant Bit Time Segment Settings
8.4.4
8.4.4.1
Synchronization
Jump Width
Time Segment 1
TSEG1
Time Segment 2
TSEG2
SJW
5 .. 10
4 .. 9
2
1
1 .. 2
0 .. 1
4 .. 11
3 .. 10
3
2
1 .. 3
0 .. 2
5 .. 12
4 .. 11
4
3
1 .. 4
0 .. 3
6 .. 13
5 .. 12
5
4
1 .. 4
0 .. 3
7 .. 14
6 .. 13
6
5
1 .. 4
0 .. 3
8 .. 15
7 .. 14
7
6
1 .. 4
0 .. 3
9 .. 16
8 .. 15
8
7
1 .. 4
0 .. 3
Modes of Operation
Normal System Operating Modes
The MSCAN module behaves as described within this specification in all normal system operating modes.
Write restrictions exist for some registers.
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8.4.4.2
Special System Operating Modes
The MSCAN module behaves as described within this specification in all special system operating modes.
Write restrictions which exist on specific registers in normal modes are lifted for test purposes in special
modes.
8.4.4.3
Emulation Modes
In all emulation modes, the MSCAN module behaves just like in normal system operating modes as
described within this specification.
8.4.4.4
Listen-Only Mode
In an optional CAN bus monitoring mode (listen-only), the CAN node is able to receive valid data frames
and valid remote frames, but it sends only “recessive” bits on the CAN bus. In addition, it cannot start a
transmission.
If the MAC sub-layer is required to send a “dominant” bit (ACK bit, overload flag, or active error flag), the
bit is rerouted internally so that the MAC sub-layer monitors this “dominant” bit, although the CAN bus
may remain in recessive state externally.
8.4.4.5
MSCAN Initialization Mode
The MSCAN enters initialization mode when it is enabled (CANE=1).
When entering initialization mode during operation, any on-going transmission or reception is
immediately aborted and synchronization to the CAN bus is lost, potentially causing CAN protocol
violations. To protect the CAN bus system from fatal consequences of violations, the MSCAN
immediately drives TXCAN into a recessive state.
NOTE
The user is responsible for ensuring that the MSCAN is not active when
initialization mode is entered. The recommended procedure is to bring the
MSCAN into sleep mode (SLPRQ = 1 and SLPAK = 1) before setting the
INITRQ bit in the CANCTL0 register. Otherwise, the abort of an on-going
message can cause an error condition and can impact other CAN bus
devices.
In initialization mode, the MSCAN is stopped. However, interface registers remain accessible. This mode
is used to reset the CANCTL0, CANRFLG, CANRIER, CANTFLG, CANTIER, CANTARQ,
CANTAAK, and CANTBSEL registers to their default values. In addition, the MSCAN enables the
configuration of the CANBTR0, CANBTR1 bit timing registers; CANIDAC; and the CANIDAR,
CANIDMR message filters. See Section 8.3.2.1, “MSCAN Control Register 0 (CANCTL0),” for a
detailed description of the initialization mode.
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Bus Clock Domain
CAN Clock Domain
INITRQ
SYNC
sync.
INITRQ
sync.
SYNC
INITAK
CPU
Init Request
INITAK
Flag
INITAK
INIT
Flag
Figure 8-45. Initialization Request/Acknowledge Cycle
Due to independent clock domains within the MSCAN, INITRQ must be synchronized to all domains by
using a special handshake mechanism. This handshake causes additional synchronization delay (see
Section Figure 8-45., “Initialization Request/Acknowledge Cycle”).
If there is no message transfer ongoing on the CAN bus, the minimum delay will be two additional bus
clocks and three additional CAN clocks. When all parts of the MSCAN are in initialization mode, the
INITAK flag is set. The application software must use INITAK as a handshake indication for the request
(INITRQ) to go into initialization mode.
NOTE
The CPU cannot clear INITRQ before initialization mode (INITRQ = 1 and
INITAK = 1) is active.
8.4.5
Low-Power Options
If the MSCAN is disabled (CANE = 0), the MSCAN clocks are stopped for power saving.
If the MSCAN is enabled (CANE = 1), the MSCAN has two additional modes with reduced power
consumption, compared to normal mode: sleep and power down mode. In sleep mode, power consumption
is reduced by stopping all clocks except those to access the registers from the CPU side. In power down
mode, all clocks are stopped and no power is consumed.
Table 8-38 summarizes the combinations of MSCAN and CPU modes. A particular combination of modes
is entered by the given settings on the CSWAI and SLPRQ/SLPAK bits.
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Table 8-38. CPU vs. MSCAN Operating Modes
MSCAN Mode
Reduced Power Consumption
CPU Mode
Normal
Sleep
RUN
CSWAI = X(1)
SLPRQ = 0
SLPAK = 0
CSWAI = X
SLPRQ = 1
SLPAK = 1
WAIT
CSWAI = 0
SLPRQ = 0
SLPAK = 0
CSWAI = 0
SLPRQ = 1
SLPAK = 1
STOP
Power Down
Disabled
(CANE=0)
CSWAI = X
SLPRQ = X
SLPAK = X
CSWAI = 1
SLPRQ = X
SLPAK = X
CSWAI = X
SLPRQ = X
SLPAK = X
CSWAI = X
SLPRQ = X
SLPAK = X
CSWAI = X
SLPRQ = X
SLPAK = X
1. ‘X’ means don’t care.
8.4.5.1
Operation in Run Mode
As shown in Table 8-38, only MSCAN sleep mode is available as low power option when the CPU is in
run mode.
8.4.5.2
Operation in Wait Mode
The WAI instruction puts the MCU in a low power consumption stand-by mode. If the CSWAI bit is set,
additional power can be saved in power down mode because the CPU clocks are stopped. After leaving
this power down mode, the MSCAN restarts and enters normal mode again.
While the CPU is in wait mode, the MSCAN can be operated in normal mode and generate interrupts
(registers can be accessed via background debug mode).
8.4.5.3
Operation in Stop Mode
The STOP instruction puts the MCU in a low power consumption stand-by mode. In stop mode, the
MSCAN is set in power down mode regardless of the value of the SLPRQ/SLPAK and CSWAI bits
(Table 8-38).
8.4.5.4
MSCAN Normal Mode
This is a non-power-saving mode. Enabling the MSCAN puts the module from disabled mode into normal
mode. In this mode the module can either be in initialization mode or out of initialization mode. See
Section 8.4.4.5, “MSCAN Initialization Mode”.
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8.4.5.5
MSCAN Sleep Mode
The CPU can request the MSCAN to enter this low power mode by asserting the SLPRQ bit in the
CANCTL0 register. The time when the MSCAN enters sleep mode depends on a fixed synchronization
delay and its current activity:
• If there are one or more message buffers scheduled for transmission (TXEx = 0), the MSCAN will
continue to transmit until all transmit message buffers are empty (TXEx = 1, transmitted
successfully or aborted) and then goes into sleep mode.
• If the MSCAN is receiving, it continues to receive and goes into sleep mode as soon as the CAN
bus next becomes idle.
• If the MSCAN is neither transmitting nor receiving, it immediately goes into sleep mode.
Bus Clock Domain
CAN Clock Domain
SLPRQ
SYNC
sync.
SLPRQ
sync.
SYNC
SLPAK
CPU
Sleep Request
SLPAK
Flag
SLPAK
SLPRQ
Flag
MSCAN
in Sleep Mode
Figure 8-46. Sleep Request / Acknowledge Cycle
NOTE
The application software must avoid setting up a transmission (by clearing
one or more TXEx flag(s)) and immediately request sleep mode (by setting
SLPRQ). Whether the MSCAN starts transmitting or goes into sleep mode
directly depends on the exact sequence of operations.
If sleep mode is active, the SLPRQ and SLPAK bits are set (Figure 8-46). The application software must
use SLPAK as a handshake indication for the request (SLPRQ) to go into sleep mode.
When in sleep mode (SLPRQ = 1 and SLPAK = 1), the MSCAN stops its internal clocks. However, clocks
that allow register accesses from the CPU side continue to run.
If the MSCAN is in bus-off state, it stops counting the 128 occurrences of 11 consecutive recessive bits
due to the stopped clocks. TXCAN remains in a recessive state. If RXF = 1, the message can be read and
RXF can be cleared. Shifting a new message into the foreground buffer of the receiver FIFO (RxFG) does
not take place while in sleep mode.
It is possible to access the transmit buffers and to clear the associated TXE flags. No message abort takes
place while in sleep mode.
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If the WUPE bit in CANCTL0 is not asserted, the MSCAN will mask any activity it detects on CAN.
RXCAN is therefore held internally in a recessive state. This locks the MSCAN in sleep mode. WUPE
must be set before entering sleep mode to take effect.
The MSCAN is able to leave sleep mode (wake up) only when:
• CAN bus activity occurs and WUPE = 1
or
• the CPU clears the SLPRQ bit
NOTE
The CPU cannot clear the SLPRQ bit before sleep mode (SLPRQ = 1 and
SLPAK = 1) is active.
After wake-up, the MSCAN waits for 11 consecutive recessive bits to synchronize to the CAN bus. As a
consequence, if the MSCAN is woken-up by a CAN frame, this frame is not received.
The receive message buffers (RxFG and RxBG) contain messages if they were received before sleep mode
was entered. All pending actions will be executed upon wake-up; copying of RxBG into RxFG, message
aborts and message transmissions. If the MSCAN remains in bus-off state after sleep mode was exited, it
continues counting the 128 occurrences of 11 consecutive recessive bits.
8.4.5.6
MSCAN Power Down Mode
The MSCAN is in power down mode (Table 8-38) when
• CPU is in stop mode
or
• CPU is in wait mode and the CSWAI bit is set
When entering the power down mode, the MSCAN immediately stops all ongoing transmissions and
receptions, potentially causing CAN protocol violations. To protect the CAN bus system from fatal
consequences of violations to the above rule, the MSCAN immediately drives TXCAN into a recessive
state.
NOTE
The user is responsible for ensuring that the MSCAN is not active when
power down mode is entered. The recommended procedure is to bring the
MSCAN into Sleep mode before the STOP or WAI instruction (if CSWAI
is set) is executed. Otherwise, the abort of an ongoing message can cause an
error condition and impact other CAN bus devices.
In power down mode, all clocks are stopped and no registers can be accessed. If the MSCAN was not in
sleep mode before power down mode became active, the module performs an internal recovery cycle after
powering up. This causes some fixed delay before the module enters normal mode again.
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8.4.5.7
Disabled Mode
The MSCAN is in disabled mode out of reset (CANE=0). All module clocks are stopped for power saving,
however the register map can still be accessed as specified.
8.4.5.8
Programmable Wake-Up Function
The MSCAN can be programmed to wake up from sleep or power down mode as soon as CAN bus activity
is detected (see control bit WUPE in MSCAN Control Register 0 (CANCTL0). The sensitivity to existing
CAN bus action can be modified by applying a low-pass filter function to the RXCAN input line (see
control bit WUPM in Section 8.3.2.2, “MSCAN Control Register 1 (CANCTL1)”).
This feature can be used to protect the MSCAN from wake-up due to short glitches on the CAN bus lines.
Such glitches can result from—for example—electromagnetic interference within noisy environments.
8.4.6
Reset Initialization
The reset state of each individual bit is listed in Section 8.3.2, “Register Descriptions,” which details all
the registers and their bit-fields.
8.4.7
Interrupts
This section describes all interrupts originated by the MSCAN. It documents the enable bits and generated
flags. Each interrupt is listed and described separately.
8.4.7.1
Description of Interrupt Operation
The MSCAN supports four interrupt vectors (see Table 8-39), any of which can be individually masked
(for details see Section 8.3.2.6, “MSCAN Receiver Interrupt Enable Register (CANRIER)” to
Section 8.3.2.8, “MSCAN Transmitter Interrupt Enable Register (CANTIER)”).
NOTE
The dedicated interrupt vector addresses are defined in the Resets and
Interrupts chapter.
Table 8-39. Interrupt Vectors
Interrupt Source
8.4.7.2
CCR Mask
Local Enable
Wake-Up Interrupt (WUPIF)
I bit
CANRIER (WUPIE)
Error Interrupts Interrupt (CSCIF, OVRIF)
I bit
CANRIER (CSCIE, OVRIE)
Receive Interrupt (RXF)
I bit
CANRIER (RXFIE)
Transmit Interrupts (TXE[2:0])
I bit
CANTIER (TXEIE[2:0])
Transmit Interrupt
At least one of the three transmit buffers is empty (not scheduled) and can be loaded to schedule a message
for transmission. The TXEx flag of the empty message buffer is set.
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8.4.7.3
Receive Interrupt
A message is successfully received and shifted into the foreground buffer (RxFG) of the receiver FIFO.
This interrupt is generated immediately after receiving the EOF symbol. The RXF flag is set. If there are
multiple messages in the receiver FIFO, the RXF flag is set as soon as the next message is shifted to the
foreground buffer.
8.4.7.4
Wake-Up Interrupt
A wake-up interrupt is generated if activity on the CAN bus occurs during MSCAN sleep or power-down
mode.
NOTE
This interrupt can only occur if the MSCAN was in sleep mode (SLPRQ =
1 and SLPAK = 1) before entering power down mode, the wake-up option
is enabled (WUPE = 1), and the wake-up interrupt is enabled (WUPIE = 1).
8.4.7.5
Error Interrupt
An error interrupt is generated if an overrun of the receiver FIFO, error, warning, or bus-off condition
occurrs. MSCAN Receiver Flag Register (CANRFLG) indicates one of the following conditions:
• Overrun — An overrun condition of the receiver FIFO as described in Section 8.4.2.3, “Receive
Structures,” occurred.
• CAN Status Change — The actual value of the transmit and receive error counters control the
CAN bus state of the MSCAN. As soon as the error counters skip into a critical range (Tx/Rxwarning, Tx/Rx-error, bus-off) the MSCAN flags an error condition. The status change, which
caused the error condition, is indicated by the TSTAT and RSTAT flags (see Section 8.3.2.5,
“MSCAN Receiver Flag Register (CANRFLG)” and Section 8.3.2.6, “MSCAN Receiver Interrupt
Enable Register (CANRIER)”).
8.4.7.6
Interrupt Acknowledge
Interrupts are directly associated with one or more status flags in either the MSCAN Receiver Flag Register
(CANRFLG) or the MSCAN Transmitter Flag Register (CANTFLG). Interrupts are pending as long as
one of the corresponding flags is set. The flags in CANRFLG and CANTFLG must be reset within the
interrupt handler to handshake the interrupt. The flags are reset by writing a 1 to the corresponding bit
position. A flag cannot be cleared if the respective condition prevails.
NOTE
It must be guaranteed that the CPU clears only the bit causing the current
interrupt. For this reason, bit manipulation instructions (BSET) must not be
used to clear interrupt flags. These instructions may cause accidental
clearing of interrupt flags which are set after entering the current interrupt
service routine.
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8.5
8.5.1
Initialization/Application Information
MSCAN initialization
The procedure to initially start up the MSCAN module out of reset is as follows:
1. Assert CANE
2. Write to the configuration registers in initialization mode
3. Clear INITRQ to leave initialization mode
If the configuration of registers which are only writable in initialization mode shall be changed:
1. Bring the module into sleep mode by setting SLPRQ and awaiting SLPAK to assert after the CAN
bus becomes idle.
2. Enter initialization mode: assert INITRQ and await INITAK
3. Write to the configuration registers in initialization mode
4. Clear INITRQ to leave initialization mode and continue
8.5.2
Bus-Off Recovery
The bus-off recovery is user configurable. The bus-off state can either be left automatically or on user
request.
For reasons of backwards compatibility, the MSCAN defaults to automatic recovery after reset. In this
case, the MSCAN will become error active again after counting 128 occurrences of 11 consecutive
recessive bits on the CAN bus (see the Bosch CAN specification for details).
If the MSCAN is configured for user request (BORM set in MSCAN Control Register 1 (CANCTL1)), the
recovery from bus-off starts after both independent events have become true:
• 128 occurrences of 11 consecutive recessive bits on the CAN bus have been monitored
• BOHOLD in MSCAN Miscellaneous Register (CANMISC) has been cleared by the user
These two events may occur in any order.
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Chapter 9
Analog-to-Digital Converter (ADC12B10C)
Revision History
Version
Number
Revision
Date
Effective
Date
V01.00
25 July 2007
25 July 2007
V01.01
14 Sept 2007
14 Sept 2007
Author
Description of Changes
Initial version
Added reserved registers at the end the memory map.
V01.02
1 Oct 2007
1 Oct 2007
Added following mention where applies:
(n conversion number, NOT channel number!)
V01.03
9 Oct 2007
9 Oct 2007
Modified table “Analog Input Channel Select Coding” due to
new customer feature (SPECIAL17).
9.1
Introduction
The ADC12B10C is a 10-channel, 12-bit, multiplexed input successive approximation analog-to-digital
converter. Refer to device electrical specifications for ATD accuracy.
9.1.1
•
•
•
•
•
•
•
•
•
•
•
•
•
Features
8-, 10-, or 12-bit resolution.
Conversion in Stop Mode using internally generated clock
Automatic return to low power after conversion sequence
Automatic compare with interrupt for higher than or less/equal than programmable value
Programmable sample time.
Left/right justified result data.
External trigger control.
Sequence complete interrupt.
Analog input multiplexer for 10 analog input channels.
Special conversions for VRH, VRL, (VRL+VRH)/2.
1-to-10 conversion sequence lengths.
Continuous conversion mode.
Multiple channel scans.
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•
•
Configurable external trigger functionality on any AD channel or any of four additional trigger
inputs. The four additional trigger inputs can be chip external or internal. Refer to device
specification for availability and connectivity.
Configurable location for channel wrap around (when converting multiple channels in a sequence).
9.1.2
Modes of Operation
9.1.2.1
Conversion Modes
There is software programmable selection between performing single or continuous conversion on a
single channel or multiple channels.
9.1.2.2
•
•
•
MCU Operating Modes
Stop Mode
— ICLKSTP=0 (in ATDCTL2 register)
Entering Stop Mode aborts any conversion sequence in progress and if a sequence was aborted
restarts it after exiting stop mode. This has the same effect/consequences as starting a
conversion sequence with write to ATDCTL5. So after exiting from stop mode with a
previously aborted sequence all flags are cleared etc.
— ICLKSTP=1 (in ATDCTL2 register)
A/D conversion sequence seamless continues in Stop Mode based on the internally generated
clock ICLK as ATD clock. For conversions during transition from Run to Stop Mode or vice
versa the result is not written to the results register, no CCF flag is set and no compare is done.
When converting in Stop Mode (ICLKSTP=1) an ATD Stop Recovery time tATDSTPRCV is
required to switch back to bus clock based ATDCLK when leaving Stop Mode. Do not access
ATD registers during this time.
Wait Mode
ADC12B10C behaves same in Run and Wait Mode. For reduced power consumption continuous
conversions should be aborted before entering Wait mode.
Freeze Mode
In Freeze Mode the ADC12B10C will either continue or finish or stop converting according to the
FRZ1 and FRZ0 bits. This is useful for debugging and emulation.
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9.1.3
Block Diagram
Bus Clock
ICLK
Clock
Prescaler
Internal
Clock
ATD Clock
ETRIG0
ETRIG1
ETRIG2
Trigger
Mux
Mode and
ATD_12B10C
Sequence Complete
Interrupt
Compare Interrupt
Timing Control
ETRIG3
(See device specification for availability
and connectivity)
ATDCTL1
ATDDIEN
VDDA
VSSA
Successive
Approximation
Register (SAR)
and DAC
VRH
VRL
Results
ATD 0
ATD 1
ATD 2
ATD 3
ATD 4
ATD 5
ATD 6
ATD 7
ATD 8
ATD 9
+
Sample & Hold
AN9
-
AN8
AN7
Analog
MUX
Comparator
AN6
AN5
AN4
AN3
AN2
AN1
AN0
Figure 9-1. ADC12B10C Block Diagram
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9.2
Signal Description
This section lists all inputs to the ADC12B10C block.
9.2.1
9.2.1.1
Detailed Signal Descriptions
ANx (x = 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
This pin serves as the analog input Channel x. It can also be configured as digital port or external trigger
for the ATD conversion.
9.2.1.2
ETRIG3, ETRIG2, ETRIG1, ETRIG0
These inputs can be configured to serve as an external trigger for the ATD conversion.
Refer to device specification for availability and connection of these inputs!
9.2.1.3
VRH, VRL
VRH is the high reference voltage, VRL is the low reference voltage for ATD conversion.
9.2.1.4
VDDA, VSSA
These pins are the power supplies for the analog circuitry of the ADC12B10C block.
9.3
Memory Map and Register Definition
This section provides a detailed description of all registers accessible in the ADC12B10C.
9.3.1
Module Memory Map
Figure 9-2 gives an overview on all ADC12B10C registers.
NOTE
Register Address = Base Address + Address Offset, where the Base Address
is defined at the MCU level and the Address Offset is defined at the module
level.
Address
Name
0x0000
ATDCTL0
0x0001
ATDCTL1
0x0002
ATDCTL2
Bit 7
R
Reserved
W
R
ETRIGSEL
W
R
0
W
6
0
5
0
SRES1
SRES0
AFFC
4
0
3
2
1
Bit 0
WRAP3
WRAP2
WRAP1
WRAP0
SMP_DIS ETRIGCH3 ETRIGCH2 ETRIGCH1 ETRIGCH0
ICLKSTP ETRIGLE
ETRIGP
ETRIGE
ASCIE
ACMPIE
= Unimplemented or Reserved
Figure 9-2. ADC12B10C Register Summary (Sheet 1 of 3)
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Address
0x0003
0x0004
0x0005
0x0006
0x0007
0x0008
0x0009
0x000A
0x000B
0x000C
Name
R
ATDCTL3
W
R
ATDCTL4
W
R
ATDCTL5
W
R
ATDSTAT0
W
R
Unimplemented
W
R
ATDCMPEH
W
R
W
R
ATDSTAT2H
W
R
ATDSTAT2L
W
R
ATDDIENH
W
6
5
4
3
2
1
Bit 0
DJM
S8C
S4C
S2C
S1C
FIFO
FRZ1
FRZ0
SMP2
SMP1
SMP0
SC
SCAN
MULT
ETORF
FIFOR
0
SCF
0
PRS[4:0]
0x0010
ATDDR0
0x0012
ATDDR1
0x0014
ATDDR2
0x0016
ATDDR3
0x0018
ATDDR4
0x001A
ATDDR5
0x001C
ATDDR6
0x001E
ATDDR7
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
CC
CB
CA
CC3
CC2
CC1
CC0
0
0
0
0
0
0
0
0
0
0
0
0
0
CMPE[9:8]
CMPE[7:0]
0
0
0
0
0
0
CCF[9:8]
CCF[7:0]
0
0
0
0
0
ATDDIENL
0x000F ATDCMPHTL
CD
0
ATDCMPEL
R
W
R
0x000E ATDCMPHTH
W
0x000D
Bit 7
0
IEN[9:8]
IEN[7:0]
0
0
0
0
0
0
CMPHT[9:8]
CMPHT[7:0]
See Section 9.3.2.12.1, “Left Justified Result Data (DJM=0)”
and Section 9.3.2.12.2, “Right Justified Result Data (DJM=1)”
See Section 9.3.2.12.1, “Left Justified Result Data (DJM=0)”
and Section 9.3.2.12.2, “Right Justified Result Data (DJM=1)”
See Section 9.3.2.12.1, “Left Justified Result Data (DJM=0)”
and Section 9.3.2.12.2, “Right Justified Result Data (DJM=1)”
See Section 9.3.2.12.1, “Left Justified Result Data (DJM=0)”
and Section 9.3.2.12.2, “Right Justified Result Data (DJM=1)”
See Section 9.3.2.12.1, “Left Justified Result Data (DJM=0)”
and Section 9.3.2.12.2, “Right Justified Result Data (DJM=1)”
See Section 9.3.2.12.1, “Left Justified Result Data (DJM=0)”
and Section 9.3.2.12.2, “Right Justified Result Data (DJM=1)”
See Section 9.3.2.12.1, “Left Justified Result Data (DJM=0)”
and Section 9.3.2.12.2, “Right Justified Result Data (DJM=1)”
See Section 9.3.2.12.1, “Left Justified Result Data (DJM=0)”
and Section 9.3.2.12.2, “Right Justified Result Data (DJM=1)”
= Unimplemented or Reserved
Figure 9-2. ADC12B10C Register Summary (Sheet 2 of 3)
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Address
Name
0x0020
ATDDR8
0x0022
ATDDR9
0x0024 0x002F
Unimplemented
Bit 7
R
W
R
W
R
6
5
4
3
2
1
See Section 9.3.2.12.1, “Left Justified Result Data (DJM=0)”
and Section 9.3.2.12.2, “Right Justified Result Data (DJM=1)”
Bit 0
See Section 9.3.2.12.1, “Left Justified Result Data (DJM=0)”
and Section 9.3.2.12.2, “Right Justified Result Data (DJM=1)”
0
0
0
0
0
0
0
0
W
= Unimplemented or Reserved
Figure 9-2. ADC12B10C Register Summary (Sheet 3 of 3)
9.3.2
Register Descriptions
This section describes in address order all the ADC12B10C registers and their individual bits.
9.3.2.1
ATD Control Register 0 (ATDCTL0)
Writes to this register will abort current conversion sequence.
Module Base + 0x0000
7
R
W
Reserved
Reset
0
6
5
4
0
0
0
0
0
0
3
2
1
0
WRAP3
WRAP2
WRAP1
WRAP0
1
1
1
1
= Unimplemented or Reserved
Figure 9-3. ATD Control Register 0 (ATDCTL0)
Read: Anytime
Write: Anytime, in special modes always write 0 to Reserved Bit 7.
Table 9-1. ATDCTL0 Field Descriptions
Field
3-0
WRAP[3-0]
Description
Wrap Around Channel Select Bits — These bits determine the channel for wrap around when doing multichannel conversions. The coding is summarized in Table 9-2.
Table 9-2. Multi-Channel Wrap Around Coding
WRAP3 WRAP2 WRAP1 WRAP0
Multiple Channel Conversions (MULT = 1)
Wraparound to AN0 after Converting
0
0
0
0
Reserved(1)
0
0
0
1
AN1
0
0
1
0
AN2
0
0
1
1
AN3
0
1
0
0
AN4
0
1
0
1
AN5
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Table 9-2. Multi-Channel Wrap Around Coding
Multiple Channel Conversions (MULT = 1)
Wraparound to AN0 after Converting
WRAP3 WRAP2 WRAP1 WRAP0
0
1
1
0
AN6
0
1
1
1
AN7
1
0
0
0
AN8
1
0
0
1
AN9
1
0
1
0
AN9
1
0
1
1
AN9
1
1
0
0
AN9
1
1
0
1
AN9
1
1
1
0
AN9
1
1
1
1
1. If only AN0 should be converted use MULT=0.
9.3.2.2
AN9
ATD Control Register 1 (ATDCTL1)
Writes to this register will abort current conversion sequence.
Module Base + 0x0001
7
6
5
4
3
2
1
0
ETRIGSEL
SRES1
SRES0
SMP_DIS
ETRIGCH3
ETRIGCH2
ETRIGCH1
ETRIGCH0
0
0
1
0
1
1
1
1
R
W
Reset
Figure 9-4. ATD Control Register 1 (ATDCTL1)
Read: Anytime
Write: Anytime
Table 9-3. ATDCTL1 Field Descriptions
Field
Description
7
ETRIGSEL
External Trigger Source Select — This bit selects the external trigger source to be either one of the AD
channels or one of the ETRIG3-0 inputs. See device specification for availability and connectivity of ETRIG30 inputs. If a particular ETRIG3-0 input option is not available, writing a 1 to ETRISEL only sets the bit but has
not effect, this means that one of the AD channels (selected by ETRIGCH3-0) is configured as the source for
external trigger. The coding is summarized in Table 9-5.
6–5
SRES[1:0]
A/D Resolution Select — These bits select the resolution of A/D conversion results. See Table 9-4 for coding.
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Table 9-3. ATDCTL1 Field Descriptions (continued)
Field
Description
4
SMP_DIS
Discharge Before Sampling Bit
0 No discharge before sampling.
1 The internal sample capacitor is discharged before sampling the channel. This adds 2 ATD clock cycles to
the sampling time. This can help to detect an open circuit instead of measuring the previous sampled
channel.
3–0
External Trigger Channel Select — These bits select one of the AD channels or one of the ETRIG3-0 inputs
ETRIGCH[3:0] as source for the external trigger. The coding is summarized in Table 9-5.
Table 9-4. A/D Resolution Coding
SRES1
SRES0
A/D Resolution
0
0
8-bit data
0
1
10-bit data
1
0
12-bit data
1
1
Reserved
Table 9-5. External Trigger Channel Select Coding
ETRIGSEL
ETRIGCH3
ETRIGCH2
ETRIGCH1
ETRIGCH0
External trigger source is
0
0
0
0
0
AN0
0
0
0
0
1
AN1
0
0
0
1
0
AN2
0
0
0
1
1
AN3
0
0
1
0
0
AN4
0
0
1
0
1
AN5
0
0
1
1
0
AN6
0
0
1
1
1
AN7
0
1
0
0
0
AN8
0
1
0
0
1
AN9
0
1
0
1
0
AN9
0
1
0
1
1
AN9
0
1
1
0
0
AN9
0
1
1
0
1
AN9
0
1
1
1
0
AN9
0
1
1
1
1
AN9
1
0
0
0
0
ETRIG0(1)
1
0
0
0
1
ETRIG11
1
0
0
1
0
ETRIG21
1
0
0
1
1
ETRIG31
1
0
1
X
X
Reserved
1
1
X
X
X
Reserved
1. Only if ETRIG3-0 input option is available (see device specification), else ETRISEL is ignored, that means
external trigger source is still on one of the AD channels selected by ETRIGCH3-0
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9.3.2.3
ATD Control Register 2 (ATDCTL2)
Writes to this register will abort current conversion sequence.
Module Base + 0x0002
7
R
6
5
4
3
2
1
0
AFFC
ICLKSTP
ETRIGLE
ETRIGP
ETRIGE
ASCIE
ACMPIE
0
0
0
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 9-5. ATD Control Register 2 (ATDCTL2)
Read: Anytime
Write: Anytime
Table 9-6. ATDCTL2 Field Descriptions
Field
Description
6
AFFC
ATD Fast Flag Clear All
0 ATD flag clearing done by write 1 to respective CCF[n] flag.
1 Changes all ATD conversion complete flags to a fast clear sequence.
For compare disabled (CMPE[n]=0) a read access to the result register will cause the associated CCF[n] flag
to clear automatically.
For compare enabled (CMPE[n]=1) a write access to the result register will cause the associated CCF[n] flag
to clear automatically.
5
ICLKSTP
Internal Clock in Stop Mode Bit — This bit enables A/D conversions in stop mode. When going into stop mode
and ICLKSTP=1 the ATD conversion clock is automatically switched to the internally generated clock ICLK.
Current conversion sequence will seamless continue. Conversion speed will change from prescaled bus
frequency to the ICLK frequency (see ATD Electrical Characteristics in device description). The prescaler bits
PRS4-0 in ATDCTL4 have no effect on the ICLK frequency. For conversions during stop mode the automatic
compare interrupt or the sequence complete interrupt can be used to inform software handler about changing
A/D values. External trigger will not work while converting in stop mode. For conversions during transition from
Run to Stop Mode or vice versa the result is not written to the results register, no CCF flag is set and no compare
is done. When converting in Stop Mode (ICLKSTP=1) an ATD Stop Recovery time tATDSTPRCV is required to
switch back to bus clock based ATDCLK when leaving Stop Mode. Do not access ATD registers during this time.
0 If A/D conversion sequence is ongoing when going into stop mode, the actual conversion sequence will be
aborted and automatically restarted when exiting stop mode.
1 A/D continues to convert in stop mode using internally generated clock (ICLK)
4
ETRIGLE
External Trigger Level/Edge Control — This bit controls the sensitivity of the external trigger signal. See
Table 9-7 for details.
3
ETRIGP
External Trigger Polarity — This bit controls the polarity of the external trigger signal. See Table 9-7 for details.
2
ETRIGE
External Trigger Mode Enable — This bit enables the external trigger on one of the AD channels or one of the
ETRIG3-0 inputs as described in Table 9-5. If external trigger source is one of the AD channels, the digital input
buffer of this channel is enabled. The external trigger allows to synchronize the start of conversion with external
events. External trigger will not work while converting in stop mode.
0 Disable external trigger
1 Enable external trigger
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Analog-to-Digital Converter (ADC12B10C)
Table 9-6. ATDCTL2 Field Descriptions (continued)
Field
1
ASCIE
0
ACMPIE
Description
ATD Sequence Complete Interrupt Enable
0 ATD Sequence Complete interrupt requests are disabled.
1 ATD Sequence Complete interrupt will be requested whenever SCF=1 is set.
ATD Compare Interrupt Enable — If automatic compare is enabled for conversion n (CMPE[n]=1 in ATDCMPE
register) this bit enables the compare interrupt. If the CCF[n] flag is set (showing a successful compare for
conversion n), the compare interrupt is triggered.
0 ATD Compare interrupt requests are disabled.
1 For the conversions in a sequence for which automatic compare is enabled (CMPE[n]=1), ATD Compare
Interrupt will be requested whenever any of the respective CCF flags is set.
Table 9-7. External Trigger Configurations
9.3.2.4
ETRIGLE
ETRIGP
External Trigger Sensitivity
0
0
Falling edge
0
1
Rising edge
1
0
Low level
1
1
High level
ATD Control Register 3 (ATDCTL3)
Writes to this register will abort current conversion sequence.
Module Base + 0x0003
7
6
5
4
3
2
1
0
DJM
S8C
S4C
S2C
S1C
FIFO
FRZ1
FRZ0
0
0
1
0
0
0
0
0
R
W
Reset
= Unimplemented or Reserved
Figure 9-6. ATD Control Register 3 (ATDCTL3)
Read: Anytime
Write: Anytime
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Freescale Semiconductor
Analog-to-Digital Converter (ADC12B10C)
Table 9-8. ATDCTL3 Field Descriptions
Field
Description
7
DJM
Result Register Data Justification — Result data format is always unsigned. This bit controls justification of
conversion data in the result registers.
0 Left justified data in the result registers.
1 Right justified data in the result registers.
Table 9-9 gives examples ATD results for an input signal range between 0 and 5.12 Volts.
6–3
S8C, S4C,
S2C, S1C
Conversion Sequence Length — These bits control the number of conversions per sequence. Table 9-10
shows all combinations. At reset, S4C is set to 1 (sequence length is 4). This is to maintain software continuity
to HC12 family.
2
FIFO
Result Register FIFO Mode — If this bit is zero (non-FIFO mode), the A/D conversion results map into the result
registers based on the conversion sequence; the result of the first conversion appears in the first result register
(ATDDR0), the second result in the second result register (ATDDR1), and so on.
If this bit is one (FIFO mode) the conversion counter is not reset at the beginning or ending of a conversion
sequence; sequential conversion results are placed in consecutive result registers. In a continuously scanning
conversion sequence, the result register counter will wrap around when it reaches the end of the result register
file. The conversion counter value (CC3-0 in ATDSTAT0) can be used to determine where in the result register
file, the current conversion result will be placed.
Aborting a conversion or starting a new conversion clears the conversion counter even if FIFO=1. So the first
result of a new conversion sequence, started by writing to ATDCTL5, will always be place in the first result register
(ATDDDR0). Intended usage of FIFO mode is continuos conversion (SCAN=1) or triggered conversion
(ETRIG=1).
Which result registers hold valid data can be tracked using the conversion complete flags. Fast flag clear mode
may or may not be useful in a particular application to track valid data.
If this bit is one, automatic compare of result registers is always disabled, that is ADC12B10C will behave as if
ACMPIE and all CPME[n] were zero.
0 Conversion results are placed in the corresponding result register up to the selected sequence length.
1 Conversion results are placed in consecutive result registers (wrap around at end).
1–0
FRZ[1:0]
Background Debug Freeze Enable — When debugging an application, it is useful in many cases to have the
ATD pause when a breakpoint (Freeze Mode) is encountered. These 2 bits determine how the ATD will respond
to a breakpoint as shown in Table 9-11. Leakage onto the storage node and comparator reference capacitors
may compromise the accuracy of an immediately frozen conversion depending on the length of the freeze period.
S12P-Family Reference Manual, Rev. 1.13
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Analog-to-Digital Converter (ADC12B10C)
Table 9-9. Examples of ideal decimal ATD Results
Input Signal
VRL = 0 Volts
VRH = 5.12 Volts
8-Bit
Codes
(resolution=20mV)
10-Bit
Codes
(resolution=5mV)
12-Bit
Codes
(transfer curve has
1.25mV offset)
(resolution=1.25mV)
5.120 Volts
...
0.022
0.020
0.018
0.016
0.014
0.012
0.010
0.008
0.006
0.004
0.003
0.002
0.000
255
...
1
1
1
1
1
1
1
0
0
0
0
0
0
1023
...
4
4
4
3
3
2
2
2
1
1
0
0
0
4095
...
17
16
14
12
11
9
8
6
4
3
2
1
0
Table 9-10. Conversion Sequence Length Coding
S8C
S4C
S2C
S1C
Number of Conversions
per Sequence
0
0
0
0
10
0
0
0
1
1
0
0
1
0
2
0
0
1
1
3
0
1
0
0
4
0
1
0
1
5
0
1
1
0
6
0
1
1
1
7
1
0
0
0
8
1
0
0
1
9
1
0
1
0
10
1
0
1
1
10
1
1
0
0
10
1
1
0
1
10
1
1
1
0
10
1
1
1
1
10
Table 9-11. ATD Behavior in Freeze Mode (Breakpoint)
FRZ1
FRZ0
0
0
Behavior in Freeze Mode
Continue conversion
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Freescale Semiconductor
Analog-to-Digital Converter (ADC12B10C)
Table 9-11. ATD Behavior in Freeze Mode (Breakpoint)
9.3.2.5
FRZ1
FRZ0
Behavior in Freeze Mode
0
1
Reserved
1
0
Finish current conversion, then freeze
1
1
Freeze Immediately
ATD Control Register 4 (ATDCTL4)
Writes to this register will abort current conversion sequence.
Module Base + 0x0004
7
6
5
SMP2
SMP1
SMP0
0
0
0
4
3
2
1
0
0
1
R
PRS[4:0]
W
Reset
0
0
1
Figure 9-7. ATD Control Register 4 (ATDCTL4)
Read: Anytime
Write: Anytime
Table 9-12. ATDCTL4 Field Descriptions
Field
Description
7–5
SMP[2:0]
Sample Time Select — These three bits select the length of the sample time in units of ATD conversion clock
cycles. Note that the ATD conversion clock period is itself a function of the prescaler value (bits PRS4-0). Table 913 lists the available sample time lengths.
4–0
PRS[4:0]
ATD Clock Prescaler — These 5 bits are the binary prescaler value PRS. The ATD conversion clock frequency
is calculated as follows:
f BUS
f ATDCLK = ------------------------------------2 × ( PRS + 1 )
Refer to Device Specification for allowed frequency range of fATDCLK.
Table 9-13. Sample Time Select
SMP2
SMP1
SMP0
Sample Time
in Number of
ATD Clock Cycles
0
0
0
4
0
0
1
6
0
1
0
8
0
1
1
10
1
0
0
12
1
0
1
16
1
1
0
20
1
1
1
24
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Analog-to-Digital Converter (ADC12B10C)
9.3.2.6
ATD Control Register 5 (ATDCTL5)
Writes to this register will abort current conversion sequence and start a new conversion sequence. If
external trigger is enabled (ETRIGE=1) an initial write to ATDCTL5 is required to allow starting of a
conversion sequence which will then occur on each trigger event. Start of conversion means the beginning
of the sampling phase.
Module Base + 0x0005
7
R
6
5
4
3
2
1
0
SC
SCAN
MULT
CD
CC
CB
CA
0
0
0
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 9-8. ATD Control Register 5 (ATDCTL5)
Read: Anytime
Write: Anytime
Table 9-14. ATDCTL5 Field Descriptions
Field
Description
6
SC
Special Channel Conversion Bit — If this bit is set, then special channel conversion can be selected using CD,
CC, CB and CA of ATDCTL5. Table 9-15 lists the coding.
0 Special channel conversions disabled
1 Special channel conversions enabled
5
SCAN
Continuous Conversion Sequence Mode — This bit selects whether conversion sequences are performed
continuously or only once. If external trigger is enabled (ETRIGE=1) setting this bit has no effect, that means
external trigger always starts a single conversion sequence.
0 Single conversion sequence
1 Continuous conversion sequences (scan mode)
4
MULT
Multi-Channel Sample Mode — When MULT is 0, the ATD sequence controller samples only from the specified
analog input channel for an entire conversion sequence. The analog channel is selected by channel selection
code (control bits CD/CC/CB/CA located in ATDCTL5). When MULT is 1, the ATD sequence controller samples
across channels. The number of channels sampled is determined by the sequence length value (S8C, S4C, S2C,
S1C). The first analog channel examined is determined by channel selection code (CD, CC, CB, CA control bits);
subsequent channels sampled in the sequence are determined by incrementing the channel selection code or
wrapping around to AN0 (channel 0).
0 Sample only one channel
1 Sample across several channels
3–0
CD, CC,
CB, CA
Analog Input Channel Select Code — These bits select the analog input channel(s) whose signals are
sampled and converted to digital codes. Table 9-15 lists the coding used to select the various analog input
channels.
In the case of single channel conversions (MULT=0), this selection code specifies the channel to be examined.
In the case of multiple channel conversions (MULT=1), this selection code specifies the first channel to be
examined in the conversion sequence. Subsequent channels are determined by incrementing the channel
selection code or wrapping around to AN0 (after converting the channel defined by the Wrap Around Channel
Select Bits WRAP3-0 in ATDCTL0). In case of starting with a channel number higher than the one defined by
WRAP3-0 the first wrap around will be AN9 to AN0.
S12P-Family Reference Manual, Rev. 1.13
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Freescale Semiconductor
Analog-to-Digital Converter (ADC12B10C)
Table 9-15. Analog Input Channel Select Coding
SC
CD
CC
CB
CA
Analog Input
Channel
0
0
0
0
0
AN0
0
0
0
1
AN1
0
0
1
0
AN2
0
0
1
1
AN3
0
1
0
0
AN4
0
1
0
1
AN5
0
1
1
0
AN6
0
1
1
1
AN7
1
0
0
0
AN8
1
0
0
1
AN9
1
0
1
0
AN9
1
0
1
1
AN9
1
1
0
0
AN9
1
1
0
1
AN9
1
1
1
0
AN9
1
9.3.2.7
1
1
1
1
AN9
0
0
0
0
Reserved
0
0
0
1
SPECIAL17
0
0
1
X
Reserved
0
1
0
0
VRH
0
1
0
1
VRL
0
1
1
0
(VRH+VRL) / 2
0
1
1
1
Reserved
1
X
X
X
Reserved
ATD Status Register 0 (ATDSTAT0)
This register contains the Sequence Complete Flag, overrun flags for external trigger and FIFO mode, and
the conversion counter.
Module Base + 0x0006
7
6
R
5
4
ETORF
FIFOR
0
0
0
SCF
3
2
1
0
CC3
CC2
CC1
CC0
0
0
0
0
W
Reset
0
0
= Unimplemented or Reserved
Figure 9-9. ATD Status Register 0 (ATDSTAT0)
S12P-Family Reference Manual, Rev. 1.13
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319
Analog-to-Digital Converter (ADC12B10C)
Read: Anytime
Write: Anytime (No effect on (CC3, CC2, CC1, CC0))
Table 9-16. ATDSTAT0 Field Descriptions
Field
Description
7
SCF
Sequence Complete Flag — This flag is set upon completion of a conversion sequence. If conversion
sequences are continuously performed (SCAN=1), the flag is set after each one is completed. This flag is cleared
when one of the following occurs:
A) Write “1” to SCF
B) Write to ATDCTL5 (a new conversion sequence is started)
C) If AFFC=1 and read of a result register
0 Conversion sequence not completed
1 Conversion sequence has completed
5
ETORF
External Trigger Overrun Flag — While in edge trigger mode (ETRIGLE=0), if additional active edges are
detected while a conversion sequence is in process the overrun flag is set. This flag is cleared when one of the
following occurs:
A) Write “1” to ETORF
B) Write to ATDCTL0,1,2,3,4, ATDCMPE or ATDCMPHT (a conversion sequence is aborted)
C) Write to ATDCTL5 (a new conversion sequence is started)
0 No External trigger over run error has occurred
1 External trigger over run error has occurred
4
FIFOR
Result Register Over Run Flag — This bit indicates that a result register has been written to before its
associated conversion complete flag (CCF) has been cleared. This flag is most useful when using the FIFO mode
because the flag potentially indicates that result registers are out of sync with the input channels. However, it is
also practical for non-FIFO modes, and indicates that a result register has been over written before it has been
read (i.e. the old data has been lost). This flag is cleared when one of the following occurs:
A) Write “1” to FIFOR
B) Write to ATDCTL0,1,2,3,4, ATDCMPE or ATDCMPHT (a conversion sequence is aborted)
C) Write to ATDCTL5 (a new conversion sequence is started)
0 No over run has occurred
1 Overrun condition exists (result register has been written while associated CCFx flag was still set)
3–0
CC[3:0]
Conversion Counter — These 4 read-only bits are the binary value of the conversion counter. The conversion
counter points to the result register that will receive the result of the current conversion. E.g. CC3=0, CC2=1,
CC1=1, CC0=0 indicates that the result of the current conversion will be in ATD Result Register 6. If in non-FIFO
mode (FIFO=0) the conversion counter is initialized to zero at the begin and end of the conversion sequence. If
in FIFO mode (FIFO=1) the register counter is not initialized. The conversion counters wraps around when its
maximum value is reached.
Aborting a conversion or starting a new conversion clears the conversion counter even if FIFO=1.
9.3.2.8
ATD Compare Enable Register (ATDCMPE)
Writes to this register will abort current conversion sequence.
Read: Anytime
Write: Anytime
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Freescale Semiconductor
Analog-to-Digital Converter (ADC12B10C)
Module Base + 0x0008
15
14
13
12
11
10
0
0
0
0
0
0
0
0
0
0
0
R
9
8
7
6
0
4
3
2
1
0
0
0
0
0
CMPE[9:0]
W
Reset
5
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 9-10. ATD Compare Enable Register (ATDCMPE)
Table 9-17. ATDCMPE Field Descriptions
Field
Description
9–0
CMPE[9:0]
Compare Enable for Conversion Number n (n= 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) of a Sequence (n conversion
number, NOT channel number!) — These bits enable automatic compare of conversion results individually for
conversions of a sequence. The sense of each comparison is determined by the CMPHT[n] bit in the ATDCMPHT
register.
For each conversion number with CMPE[n]=1 do the following:
1) Write compare value to ATDDRn result register
2) Write compare operator with CMPHT[n] in ATDCPMHT register
CCF[n] in ATDSTAT2 register will flag individual success of any comparison.
0 No automatic compare
1 Automatic compare of results for conversion n of a sequence is enabled.
9.3.2.9
ATD Status Register 2 (ATDSTAT2)
This read-only register contains the Conversion Complete Flags CCF[9:0].
Module Base + 0x000A
R
15
14
13
12
11
10
0
0
0
0
0
0
0
0
0
0
0
0
9
8
7
6
5
4
3
2
1
0
0
0
0
0
CCF[9:0]
W
Reset
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 9-11. ATD Status Register 2 (ATDSTAT2)
Read: Anytime
Write: Anytime, no effect
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
321
Analog-to-Digital Converter (ADC12B10C)
Table 9-18. ATDSTAT2 Field Descriptions
Field
Description
9–0
CCF[9:0]
Conversion Complete Flag n (n= 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) (n conversion number, NOT channel number!)—
A conversion complete flag is set at the end of each conversion in a sequence. The flags are associated with the
conversion position in a sequence (and also the result register number). Therefore in non-fifo mode, CCF[8] is
set when the ninth conversion in a sequence is complete and the result is available in result register ATDDR8;
CCF[9] is set when the tenth conversion in a sequence is complete and the result is available in ATDDR9, and
so forth.
If automatic compare of conversion results is enabled (CMPE[n]=1 in ATDCMPE), the conversion complete flag
is only set if comparison with ATDDRn is true and if ACMPIE=1 a compare interrupt will be requested. In this
case, as the ATDDRn result register is used to hold the compare value, the result will not be stored there at the
end of the conversion but is lost.
A flag CCF[n] is cleared when one of the following occurs:
A) Write to ATDCTL5 (a new conversion sequence is started)
B) If AFFC=0, write “1” to CCF[n]
C) If AFFC=1 and CMPE[n]=0, read of result register ATDDRn
D) If AFFC=1 and CMPE[n]=1, write to result register ATDDRn
In case of a concurrent set and clear on CCF[n]: The clearing by method A) will overwrite the set. The clearing
by methods B) or C) or D) will be overwritten by the set.
0 Conversion number n not completed or successfully compared
1 If (CMPE[n]=0): Conversion number n has completed. Result is ready in ATDDRn.
If (CMPE[n]=1): Compare for conversion result number n with compare value in ATDDRn, using compare
operator CMPGT[n] is true. (No result available in ATDDRn)
9.3.2.10
ATD Input Enable Register (ATDDIEN)
Module Base + 0x000C
R
15
14
13
12
11
10
0
0
0
0
0
0
0
0
0
0
0
0
9
8
7
6
4
3
2
1
0
0
0
0
0
IEN[9:0]
W
Reset
5
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 9-12. ATD Input Enable Register (ATDDIEN)
Read: Anytime
Write: Anytime
Table 9-19. ATDDIEN Field Descriptions
Field
Description
9–0
IEN[9:0]
ATD Digital Input Enable on channel x (x= 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) — This bit controls the digital input buffer
from the analog input pin (ANx) to the digital data register.
0 Disable digital input buffer to ANx pin
1 Enable digital input buffer on ANx pin.
Note: Setting this bit will enable the corresponding digital input buffer continuously. If this bit is set while
simultaneously using it as an analog port, there is potentially increased power consumption because the
digital input buffer maybe in the linear region.
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Freescale Semiconductor
Analog-to-Digital Converter (ADC12B10C)
9.3.2.11
ATD Compare Higher Than Register (ATDCMPHT)
Writes to this register will abort current conversion sequence.
Read: Anytime
Write: Anytime
Module Base + 0x000E
R
15
14
13
12
11
10
0
0
0
0
0
0
0
0
0
0
0
0
9
8
7
6
4
3
2
1
0
0
0
0
0
CMPHT[9:0]
W
Reset
5
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 9-13. ATD Compare Higher Than Register (ATDCMPHT)
Table 9-20. ATDCMPHT Field Descriptions
Field
Description
9–0
CMPHT[9:0]
Compare Operation Higher Than Enable for conversion number n (n= 9, 8, 7, 6, 5, 4, 3, 2, 1, 0) of a
Sequence (n conversion number, NOT channel number!) — This bit selects the operator for comparison of
conversion results.
0 If result of conversion n is lower or same than compare value in ATDDRn, this is flagged in ATDSTAT2
1 If result of conversion n is higher than compare value in ATDDRn, this is flagged in ATDSTAT2
9.3.2.12
ATD Conversion Result Registers (ATDDRn)
The A/D conversion results are stored in 10 result registers. Results are always in unsigned data
representation. Left and right justification is selected using the DJM control bit in ATDCTL3.
If automatic compare of conversions results is enabled (CMPE[n]=1 in ATDCMPE), these registers must
be written with the compare values in left or right justified format depending on the actual value of the
DJM bit. In this case, as the ATDDRn register is used to hold the compare value, the result will not be
stored there at the end of the conversion but is lost.
Attention, n is the conversion number, NOT the channel number!
Read: Anytime
Write: Anytime
NOTE
For conversions not using automatic compare, results are stored in the result
registers after each conversion. In this case avoid writing to ATDDRn except
for initial values, because an A/D result might be overwritten.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
323
Analog-to-Digital Converter (ADC12B10C)
9.3.2.12.1
Left Justified Result Data (DJM=0)
Module Base +
0x0010 = ATDDR0, 0x0012 = ATDDR1, 0x0014 = ATDDR2, 0x0016 = ATDDR3
0x0018 = ATDDR4, 0x001A = ATDDR5, 0x001C = ATDDR6, 0x001E = ATDDR7
0x0020 = ATDDR8, 0x0022 = ATDDR9
15
R
W
Reset
14
13
Bit 11 Bit 10 Bit 9
0
0
0
12
11
10
9
8
7
6
5
4
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
0
3
2
1
0
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 9-14. Left justified ATD conversion result register (ATDDRn)
9.3.2.12.2
Right Justified Result Data (DJM=1)
Module Base +
0x0010 = ATDDR0, 0x0012 = ATDDR1, 0x0014 = ATDDR2, 0x0016 = ATDDR3
0x0018 = ATDDR4, 0x001A = ATDDR5, 0x001C = ATDDR6, 0x001E = ATDDR7
0x0020 = ATDDR8, 0x0022 = ATDDR9
R
15
14
13
12
0
0
0
0
0
0
0
0
W
Reset
11
10
9
Bit 11 Bit 10 Bit 9
0
0
0
8
7
6
5
4
3
2
1
0
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bi1 1
Bit 0
0
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 9-15. Right justified ATD conversion result register (ATDDRn)
Table 9-21 shows how depending on the A/D resolution the conversion result is transferred to the ATD
result registers. Compare is always done using all 12 bits of both the conversion result and the compare
value in ATDDRn.
Table 9-21. Conversion result mapping to ATDDRn
A/D
resolution
9.4
DJM
conversion result mapping to
ATDDRn
8-bit data
0
Bit[11:4] = result, Bit[3:0]=0000
8-bit data
1
Bit[7:0] = result, Bit[11:8]=0000
10-bit data
0
Bit[11:2] = result, Bit[1:0]=00
10-bit data
1
Bit[9:0] = result, Bit[11:10]=00
12-bit data
X
Bit[11:0] = result
Functional Description
The ADC12B10C is structured into an analog sub-block and a digital sub-block.
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Analog-to-Digital Converter (ADC12B10C)
9.4.1
Analog Sub-Block
The analog sub-block contains all analog electronics required to perform a single conversion. Separate
power supplies VDDA and VSSA allow to isolate noise of other MCU circuitry from the analog sub-block.
9.4.1.1
Sample and Hold Machine
The Sample and Hold (S/H) Machine accepts analog signals from the external world and stores them as
capacitor charge on a storage node.
During the sample process the analog input connects directly to the storage node.
The input analog signals are unipolar and must fall within the potential range of VSSA to VDDA.
During the hold process the analog input is disconnected from the storage node.
9.4.1.2
Analog Input Multiplexer
The analog input multiplexer connects one of the 10 external analog input channels to the sample and hold
machine.
9.4.1.3
Analog-to-Digital (A/D) Machine
The A/D Machine performs analog to digital conversions. The resolution is program selectable at either 8
or 10 or 12 bits. The A/D machine uses a successive approximation architecture. It functions by comparing
the stored analog sample potential with a series of digitally generated analog potentials. By following a
binary search algorithm, the A/D machine locates the approximating potential that is nearest to the
sampled potential.
When not converting the A/D machine is automatically powered down.
Only analog input signals within the potential range of VRL to VRH (A/D reference potentials) will result
in a non-railed digital output code.
9.4.2
Digital Sub-Block
This subsection explains some of the digital features in more detail. See Section 9.3.2, “Register
Descriptions” for all details.
9.4.2.1
External Trigger Input
The external trigger feature allows the user to synchronize ATD conversions to the external environment
events rather than relying on software to signal the ATD module when ATD conversions are to take place.
The external trigger signal (out of reset ATD channel 9, configurable in ATDCTL1) is programmable to
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Analog-to-Digital Converter (ADC12B10C)
be edge or level sensitive with polarity control. Table 9-22 gives a brief description of the different
combinations of control bits and their effect on the external trigger function.
Table 9-22. External Trigger Control Bits
ETRIGLE
ETRIGP
ETRIGE
SCAN
Description
X
X
0
0
Ignores external trigger. Performs one
conversion sequence and stops.
X
X
0
1
Ignores external trigger. Performs
continuous conversion sequences.
0
0
1
X
Falling edge triggered. Performs one
conversion sequence per trigger.
0
1
1
X
Rising edge triggered. Performs one
conversion sequence per trigger.
1
0
1
X
Trigger active low. Performs continuous
conversions while trigger is active.
1
1
1
X
Trigger active high. Performs continuous
conversions while trigger is active.
During a conversion, if additional active edges are detected the overrun error flag ETORF is set.
In either level or edge triggered modes, the first conversion begins when the trigger is received.
Once ETRIGE is enabled, conversions cannot be started by a write to ATDCTL5, but rather must be
triggered externally.
If the level mode is active and the external trigger both de-asserts and re-asserts itself during a conversion
sequence, this does not constitute an overrun. Therefore, the flag is not set. If the trigger is left asserted in
level mode while a sequence is completing, another sequence will be triggered immediately.
9.4.2.2
General-Purpose Digital Port Operation
The input channel pins can be multiplexed between analog and digital data. As analog inputs, they are
multiplexed and sampled as analog channels to the A/D converter. The analog/digital multiplex operation
is performed in the input pads. The input pad is always connected to the analog input channels of the
ADC12B10C. The input pad signal is buffered to the digital port registers. This buffer can be turned on or
off with the ATDDIEN register. This is important so that the buffer does not draw excess current when
analog potentials are presented at its input.
9.5
Resets
At reset the ADC12B10C is in a power down state. The reset state of each individual bit is listed within
the Register Description section (see Section 9.3.2, “Register Descriptions”) which details the registers
and their bit-field.
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Analog-to-Digital Converter (ADC12B10C)
9.6
Interrupts
The interrupts requested by the ADC12B10C are listed in Table 9-23. Refer to MCU specification for
related vector address and priority.
Table 9-23. ATD Interrupt Vectors
Interrupt Source
CCR
Mask
Local Enable
Sequence Complete Interrupt
I bit
ASCIE in ATDCTL2
Compare Interrupt
I bit
ACMPIE in ATDCTL2
See Section 9.3.2, “Register Descriptions” for further details.
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Chapter 10
Pulse-Width Modulator (PWM8B6CV1) Block Description
10.1
Introduction
The pulse width modulation (PWM) definition is based on the HC12 PWM definitions. The PWM8B6CV1
module contains the basic features from the HC11 with some of the enhancements incorporated on the
HC12, that is center aligned output mode and four available clock sources. The PWM8B6CV1 module has
six channels with independent control of left and center aligned outputs on each channel.
Each of the six PWM channels has a programmable period and duty cycle as well as a dedicated counter.
A flexible clock select scheme allows a total of four different clock sources to be used with the counters.
Each of the modulators can create independent continuous waveforms with software-selectable duty rates
from 0% to 100%. The PWM outputs can be programmed as left aligned outputs or center aligned outputs
10.1.1
•
•
•
•
•
•
•
•
•
•
Features
Six independent PWM channels with programmable period and duty cycle
Dedicated counter for each PWM channel
Programmable PWM enable/disable for each channel
Software selection of PWM duty pulse polarity for each channel
Period and duty cycle are double buffered. Change takes effect when the end of the effective period
is reached (PWM counter reaches 0) or when the channel is disabled.
Programmable center or left aligned outputs on individual channels
Six 8-bit channel or three 16-bit channel PWM resolution
Four clock sources (A, B, SA, and SB) provide for a wide range of frequencies.
Programmable clock select logic
Emergency shutdown
10.1.2
Modes of Operation
There is a software programmable option for low power consumption in wait mode that disables the input
clock to the prescaler.
In freeze mode there is a software programmable option to disable the input clock to the prescaler. This is
useful for emulation.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
10.1.3
Block Diagram
PWM8B6C
PWM Channels
Channel 5
Bus Clock
Clock Select
PWM Clock
Period and Duty
PWM5
Counter
Channel 4
Period and Duty
PWM4
Counter
Control
Channel 3
Period and Duty
PWM3
Counter
Channel 2
Enable
Period and Duty
PWM2
Counter
Channel 1
Polarity
Period and Duty
Alignment
PWM1
Counter
Channel 0
Period and Duty
PWM0
Counter
Figure 10-1. PWM8B6CV1 Block Diagram
10.2
External Signal Description
The PWM8B6CV1 module has a total of six external pins.
10.2.1
PWM5 — Pulse Width Modulator Channel 5 Pin
This pin serves as waveform output of PWM channel 5 and as an input for the emergency shutdown
feature.
10.2.2
PWM4 — Pulse Width Modulator Channel 4 Pin
This pin serves as waveform output of PWM channel 4.
10.2.3
PWM3 — Pulse Width Modulator Channel 3 Pin
This pin serves as waveform output of PWM channel 3.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
10.2.4
PWM2 — Pulse Width Modulator Channel 2 Pin
This pin serves as waveform output of PWM channel 2.
10.2.5
PWM1 — Pulse Width Modulator Channel 1 Pin
This pin serves as waveform output of PWM channel 1.
10.2.6
PWM0 — Pulse Width Modulator Channel 0 Pin
This pin serves as waveform output of PWM channel 0.
10.3
Memory Map and Register Definition
This subsection describes in detail all the registers and register bits in the PWM8B6CV1 module.
The special-purpose registers and register bit functions that would not normally be made available to
device end users, such as factory test control registers and reserved registers are clearly identified by means
of shading the appropriate portions of address maps and register diagrams. Notes explaining the reasons
for restricting access to the registers and functions are also explained in the individual register descriptions.
10.3.1
Module Memory Map
The following paragraphs describe the content of the registers in the PWM8B6CV1 module. The base
address of the PWM8B6CV1 module is determined at the MCU level when the MCU is defined. The
register decode map is fixed and begins at the first address of the module address offset. Table 10-1 shows
the registers associated with the PWM and their relative offset from the base address. The register detail
description follows the order in which they appear in the register map.
Reserved bits within a register will always read as 0 and the write will be unimplemented. Unimplemented
functions are indicated by shading the bit.
Table 10-1 shows the memory map for the PWM8B6CV1 module.
NOTE
Register address = base address + address offset, where the base address is
defined at the MCU level and the address offset is defined at the module
level.
Table 10-1. PWM8B6CV1 Memory Map
Address
Offset
Register
Access
0x0000
PWM Enable Register (PWME)
R/W
0x0001
PWM Polarity Register (PWMPOL)
R/W
0x0002
PWM Clock Select Register (PWMCLK)
R/W
0x0003
PWM Prescale Clock Select Register (PWMPRCLK)
R/W
0x0004
PWM Center Align Enable Register (PWMCAE)
R/W
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Pulse-Width Modulator (PWM8B6CV1) Block Description
Table 10-1. PWM8B6CV1 Memory Map
0x0005
0x0006
PWM Control Register (PWMCTL)
PWM Test Register (PWMTST)
R/W
(1)
R/W
(2)
0x0007
PWM Prescale Counter Register (PWMPRSC)
R/W
0x0008
PWM Scale A Register (PWMSCLA)
R/W
0x0009
PWM Scale B Register (PWMSCLB)
0x000A
R/W
(3)
R/W
(4)
R/W
PWM Scale A Counter Register (PWMSCNTA)
0x000B
PWM Scale B Counter Register (PWMSCNTB)
0x000C
PWM Channel 0 Counter Register (PWMCNT0)
R/W
0x000D
PWM Channel 1 Counter Register (PWMCNT1)
R/W
0x000E
PWM Channel 2 Counter Register (PWMCNT2)
R/W
0x000F
PWM Channel 3 Counter Register (PWMCNT3)
R/W
0x0010
PWM Channel 4 Counter Register (PWMCNT4)
R/W
0x0011
PWM Channel 5 Counter Register (PWMCNT5)
R/W
0x0012
PWM Channel 0 Period Register (PWMPER0)
R/W
0x0013
PWM Channel 1 Period Register (PWMPER1)
R/W
0x0014
PWM Channel 2 Period Register (PWMPER2)
R/W
0x0015
PWM Channel 3 Period Register (PWMPER3)
R/W
0x0016
PWM Channel 4 Period Register (PWMPER4)
R/W
0x0017
PWM Channel 5 Period Register (PWMPER5)
R/W
0x0018
PWM Channel 0 Duty Register (PWMDTY0)
R/W
0x0019
PWM Channel 1 Duty Register (PWMDTY1)
R/W
0x001A
PWM Channel 2 Duty Register (PWMDTY2)
R/W
0x001B
PWM Channel 3 Duty Register (PWMDTY3)
R/W
0x001C
PWM Channel 4 Duty Register (PWMDTY4)
R/W
0x001D
PWM Channel 5 Duty Register (PWMDTY5)
R/W
0x001E
PWM Shutdown Register (PWMSDN)
1. PWMTST is intended for factory test purposes only.
2. PWMPRSC is intended for factory test purposes only.
3. PWMSCNTA is intended for factory test purposes only.
4. PWMSCNTB is intended for factory test purposes only.
10.3.2
R/W
Register Descriptions
The following paragraphs describe in detail all the registers and register bits in the PWM8B6CV1 module.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
PWME5
PWME4
PWME3
PWME2
PWME1
PWME0
PPOL5
PPOL4
PPOL3
PPOL2
PPOL1
PPOL0
PCLK5
PCLK4
PCLK3
PCLK2
PCLK1
PCLK0
PCKB1
PCKB0
PCKA2
PCKA1
PCKA0
CAE5
CAE4
CAE2
CAE2
CAE1
CAE0
CON45
CON23
CON01
PSWAI
PFRZ
0
0
0x0000
PWME
R
W
0
0
0x0001
PWMPOL
R
W
0
0
0x0002
PWMCLK
R
W
0
0
0x0003
PWMPRCLK
R
W
0
0x0004
PWMCAE
R
W
0
0x0005
PWMCTL
R
W
0
0x0006
PWMTST
R
W
0
0
0
0
0
0
0
0
0x0007
PWMPRSC
R
W
0
0
0
0
0
0
0
0
0x0008
PWMSCLA
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x0009
PWMSCLB
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x000A
PWMSCNTA
R
W
0
0
0
0
0
0
0
0
0x000B
PWMSCNTB
R
W
0
0
0
0
0
0
0
0
0x000C
PWMCNT0
R
W
Bit 7
0
6
0
5
0
4
0
3
0
2
0
1
0
Bit 0
0
0x000D
PWMCNT1
R
W
Bit 7
0
6
0
5
0
4
0
3
0
2
0
1
0
Bit 0
0
0x000E
PWMCNT2
R
W
Bit 7
0
6
0
5
0
4
0
3
0
2
0
1
0
Bit 0
0
0x000F
PWMCNT3
R
W
Bit 7
0
6
0
5
0
4
0
3
0
2
0
1
0
Bit 0
0
PCKB2
0
0
= Unimplemented or Reserved
Figure 10-2. PWM Register Summary
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Pulse-Width Modulator (PWM8B6CV1) Block Description
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
0x0010
PWMCNT4
R
W
Bit 7
0
6
0
5
0
4
0
3
0
2
0
1
0
Bit 0
0
0x0011
PWMCNT5
R
W
Bit 7
0
6
0
5
0
4
0
3
0
2
0
1
0
Bit 0
0
0x0012
PWMPER0
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x0013
PWMPER1
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x0014
PWMPER2
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x0015
PWMPER3
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x0016
PWMPER4
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x0017
PWMPER5
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x0018
PWMDTY0
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x0019
PWMPER1
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x001A
PWMPER2
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x001B
PWMPER3
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x001C
PWMPER4
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x001D
PWMPER5
R
W
Bit 7
6
5
4
3
2
1
Bit 0
0x001E
PWMSDB
R
W
PWMIF
PWMIE
0
PWMRSTRT
PWMLVL
0
PWM5IN
PWM5INL PWM5ENA
= Unimplemented or Reserved
Figure 10-2. PWM Register Summary (continued)
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Pulse-Width Modulator (PWM8B6CV1) Block Description
10.3.2.1
PWM Enable Register (PWME)
Each PWM channel has an enable bit (PWMEx) to start its waveform output. When any of the PWMEx
bits are set (PWMEx = 1), the associated PWM output is enabled immediately. However, the actual PWM
waveform is not available on the associated PWM output until its clock source begins its next cycle due to
the synchronization of PWMEx and the clock source.
NOTE
The first PWM cycle after enabling the channel can be irregular.
An exception to this is when channels are concatenated. After concatenated mode is enabled (CONxx bits
set in PWMCTL register), enabling/disabling the corresponding 16-bit PWM channel is controlled by the
low-order PWMEx bit. In this case, the high-order bytes PWMEx bits have no effect and their
corresponding PWM output lines are disabled.
While in run mode, if all six PWM channels are disabled (PWME5–PWME0 = 0), the prescaler counter
shuts off for power savings.
Module Base + 0x0000
R
7
6
0
0
5
4
3
2
1
0
PWME5
PWME4
PWME3
PWME2
PWME1
PWME0
0
0
0
0
0
0
W
Reset
0
0
= Unimplemented or Reserved
Figure 10-3. PWM Enable Register (PWME)
Read: anytime
Write: anytime
Table 10-2. PWME Field Descriptions
Field
Description
5
PWME5
Pulse Width Channel 5 Enable
0 Pulse width channel 5 is disabled.
1 Pulse width channel 5 is enabled. The pulse modulated signal becomes available at PWM,output bit 5 when
its clock source begins its next cycle.
4
PWME4
Pulse Width Channel 4 Enable
0 Pulse width channel 4 is disabled.
1 Pulse width channel 4 is enabled. The pulse modulated signal becomes available at PWM, output bit 4 when
its clock source begins its next cycle. If CON45 = 1, then bit has no effect and PWM output line 4 is disabled.
3
PWME3
Pulse Width Channel 3 Enable
0 Pulse width channel 3 is disabled.
1 Pulse width channel 3 is enabled. The pulse modulated signal becomes available at PWM, output bit 3 when
its clock source begins its next cycle.
2
PWME2
Pulse Width Channel 2 Enable
0 Pulse width channel 2 is disabled.
1 Pulse width channel 2 is enabled. The pulse modulated signal becomes available at PWM, output bit 2 when
its clock source begins its next cycle. If CON23 = 1, then bit has no effect and PWM output line 2 is disabled.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
Table 10-2. PWME Field Descriptions (continued)
Field
Description
1
PWME1
Pulse Width Channel 1 Enable
0 Pulse width channel 1 is disabled.
1 Pulse width channel 1 is enabled. The pulse modulated signal becomes available at PWM, output bit 1 when
its clock source begins its next cycle.
0
PWME0
Pulse Width Channel 0 Enable
0 Pulse width channel 0 is disabled.
1 Pulse width channel 0 is enabled. The pulse modulated signal becomes available at PWM, output bit 0 when
its clock source begins its next cycle. If CON01 = 1, then bit has no effect and PWM output line 0 is disabled.
10.3.2.2
PWM Polarity Register (PWMPOL)
The starting polarity of each PWM channel waveform is determined by the associated PPOLx bit in the
PWMPOL register. If the polarity bit is 1, the PWM channel output is high at the beginning of the cycle
and then goes low when the duty count is reached. Conversely, if the polarity bit is 0 the output starts low
and then goes high when the duty count is reached.
Module Base + 0x0001
R
7
6
0
0
5
4
3
2
1
0
PPOL5
PPOL4
PPOL3
PPOL2
PPOL1
PPOL0
0
0
0
0
0
0
W
Reset
0
0
= Unimplemented or Reserved
Figure 10-4. PWM Polarity Register (PWMPOL)
Read: anytime
Write: anytime
NOTE
PPOLx register bits can be written anytime. If the polarity is changed while
a PWM signal is being generated, a truncated or stretched pulse can occur
during the transition
Table 10-3. PWMPOL Field Descriptions
Field
Description
5
PPOL5
Pulse Width Channel 5 Polarity
0 PWM channel 5 output is low at the beginning of the period, then goes high when the duty count is reached.
1 PWM channel 5 output is high at the beginning of the period, then goes low when the duty count is reached.
4
PPOL4
Pulse Width Channel 4 Polarity
0 PWM channel 4 output is low at the beginning of the period, then goes high when the duty count is reached.
1 PWM channel 4 output is high at the beginning of the period, then goes low when the duty count is reached.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
Table 10-3. PWMPOL Field Descriptions (continued)
Field
Description
3
PPOL3
Pulse Width Channel 3 Polarity
0 PWM channel 3 output is low at the beginning of the period, then goes high when the duty count is reached.
1 PWM channel 3 output is high at the beginning of the period, then goes low when the duty count is reached.
2
PPOL2
Pulse Width Channel 2 Polarity
0 PWM channel 2 output is low at the beginning of the period, then goes high when the duty count is reached.
1 PWM channel 2 output is high at the beginning of the period, then goes low when the duty count is reached.
1
PPOL1
Pulse Width Channel 1 Polarity
0 PWM channel 1 output is low at the beginning of the period, then goes high when the duty count is reached.
1 PWM channel 1 output is high at the beginning of the period, then goes low when the duty count is reached.
0
PPOL0
Pulse Width Channel 0 Polarity
0 PWM channel 0 output is low at the beginning of the period, then goes high when the duty count is reached
1 PWM channel 0 output is high at the beginning of the period, then goes low when the duty count is reached.
10.3.2.3
PWM Clock Select Register (PWMCLK)
Each PWM channel has a choice of two clocks to use as the clock source for that channel as described
below.
Module Base + 0x0002
R
7
6
0
0
5
4
3
2
1
0
PCLK5
PCLK4
PCLK3
PCLK2
PCLK1
PCLK0
0
0
0
0
0
0
W
Reset
0
0
= Unimplemented or Reserved
Figure 10-5. PWM Clock Select Register (PWMCLK)
Read: anytime
Write: anytime
NOTE
Register bits PCLK0 to PCLK5 can be written anytime. If a clock select is
changed while a PWM signal is being generated, a truncated or stretched
pulse can occur during the transition.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
Table 10-4. PWMCLK Field Descriptions
Field
Description
5
PCLK5
Pulse Width Channel 5 Clock Select
0 Clock A is the clock source for PWM channel 5.
1 Clock SA is the clock source for PWM channel 5.
4
PCLK4
Pulse Width Channel 4 Clock Select
0 Clock A is the clock source for PWM channel 4.
1 Clock SA is the clock source for PWM channel 4.
3
PCLK3
Pulse Width Channel 3 Clock Select
0 Clock B is the clock source for PWM channel 3.
1 Clock SB is the clock source for PWM channel 3.
2
PCLK2
Pulse Width Channel 2 Clock Select
0 Clock B is the clock source for PWM channel 2.
1 Clock SB is the clock source for PWM channel 2.
1
PCLK1
Pulse Width Channel 1 Clock Select
0 Clock A is the clock source for PWM channel 1.
1 Clock SA is the clock source for PWM channel 1.
0
PCLK0
Pulse Width Channel 0 Clock Select
0 Clock A is the clock source for PWM channel 0.
1 Clock SA is the clock source for PWM channel 0.
10.3.2.4
PWM Prescale Clock Select Register (PWMPRCLK)
This register selects the prescale clock source for clocks A and B independently.
Module Base + 0x0003
7
R
6
5
4
PCKB2
PCKB1
PCKB0
0
0
0
0
3
2
1
0
PCKA2
PCKA1
PCKA0
0
0
0
0
W
Reset
0
0
= Unimplemented or Reserved
Figure 10-6. PWM Prescaler Clock Select Register (PWMPRCLK)
Read: anytime
Write: anytime
NOTE
PCKB2–PCKB0 and PCKA2–PCKA0 register bits can be written anytime.
If the clock prescale is changed while a PWM signal is being generated, a
truncated or stretched pulse can occur during the transition.
S12P-Family Reference Manual, Rev. 1.13
338
Freescale Semiconductor
Pulse-Width Modulator (PWM8B6CV1) Block Description
Table 10-5. PWMPRCLK Field Descriptions
Field
Description
6:5
PCKB[2:0]
Prescaler Select for Clock B — Clock B is 1 of two clock sources which can be used for channels 2 or 3. These
three bits determine the rate of clock B, as shown in Table 10-6.
2:0
PCKA[2:0]
Prescaler Select for Clock A — Clock A is 1 of two clock sources which can be used for channels 0, 1, 4, or 5.
These three bits determine the rate of clock A, as shown in Table 10-7.
Table 10-6. Clock B Prescaler Selects
PCKB2
PCKB1
PCKB0
Value of Clock B
0
0
0
Bus Clock
0
0
1
Bus Clock / 2
0
1
0
Bus Clock / 4
0
1
1
Bus Clock / 8
1
0
0
Bus Clock / 16
1
0
1
Bus Clock / 32
1
1
0
Bus Clock / 64
1
1
1
Bus Clock / 128
Table 10-7. Clock A Prescaler Selects
10.3.2.5
PCKA2
PCKA1
PCKA0
Value of Clock A
0
0
0
Bus Clock
0
0
1
Bus Clock / 2
0
1
0
Bus Clock / 4
0
1
1
Bus Clock / 8
1
0
0
Bus Clock / 16
1
0
1
Bus Clock / 32
1
1
0
Bus Clock / 64
1
1
1
Bus Clock / 128
PWM Center Align Enable Register (PWMCAE)
The PWMCAE register contains six control bits for the selection of center aligned outputs or left aligned
outputs for each PWM channel. If the CAEx bit is set to a 1, the corresponding PWM output will be center
aligned. If the CAEx bit is cleared, the corresponding PWM output will be left aligned. Reference
Section 10.4.2.5, “Left Aligned Outputs,” and Section 10.4.2.6, “Center Aligned Outputs,” for a more
detailed description of the PWM output modes.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
339
Pulse-Width Modulator (PWM8B6CV1) Block Description
Module Base + 0x0004
R
7
6
0
0
5
4
3
2
1
0
CAE5
CAE4
CAE3
CAE2
CAE1
CAE0
0
0
0
0
0
0
W
Reset
0
0
= Unimplemented or Reserved
Figure 10-7. PWM Center Align Enable Register (PWMCAE)
Read: anytime
Write: anytime
NOTE
Write these bits only when the corresponding channel is disabled.
Table 10-8. PWMCAE Field Descriptions
Field
Description
5
CAE5
Center Aligned Output Mode on Channel 5
0 Channel 5 operates in left aligned output mode.
1 Channel 5 operates in center aligned output mode.
4
CAE4
Center Aligned Output Mode on Channel 4
0 Channel 4 operates in left aligned output mode.
1 Channel 4 operates in center aligned output mode.
3
CAE3
Center Aligned Output Mode on Channel 3
1 Channel 3 operates in left aligned output mode.
1 Channel 3 operates in center aligned output mode.
2
CAE2
Center Aligned Output Mode on Channel 2
0 Channel 2 operates in left aligned output mode.
1 Channel 2 operates in center aligned output mode.
1
CAE1
Center Aligned Output Mode on Channel 1
0 Channel 1 operates in left aligned output mode.
1 Channel 1 operates in center aligned output mode.
0
CAE0
Center Aligned Output Mode on Channel 0
0 Channel 0 operates in left aligned output mode.
1 Channel 0 operates in center aligned output mode.
10.3.2.6
PWM Control Register (PWMCTL)
The PWMCTL register provides for various control of the PWM module.
S12P-Family Reference Manual, Rev. 1.13
340
Freescale Semiconductor
Pulse-Width Modulator (PWM8B6CV1) Block Description
Module Base + 0x0005
7
R
6
5
4
3
2
CON45
CON23
CON01
PSWAI
PFRZ
0
0
0
0
0
0
1
0
0
0
0
0
W
Reset
0
= Unimplemented or Reserved
Figure 10-8. PWM Control Register (PWMCTL)
Read: anytime
Write: anytime
There are three control bits for concatenation, each of which is used to concatenate a pair of PWM
channels into one 16-bit channel. When channels 4 and 5 are concatenated, channel 4 registers become the
high-order bytes of the double-byte channel. When channels 2 and 3 are concatenated, channel 2 registers
become the high-order bytes of the double-byte channel. When channels 0 and 1 are concatenated,
channel 0 registers become the high-order bytes of the double-byte channel.
Reference Section 10.4.2.7, “PWM 16-Bit Functions,” for a more detailed description of the concatenation
PWM function.
NOTE
Change these bits only when both corresponding channels are disabled.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
341
Pulse-Width Modulator (PWM8B6CV1) Block Description
Table 10-9. PWMCTL Field Descriptions
Field
Description
6
CON45
Concatenate Channels 4 and 5
0 Channels 4 and 5 are separate 8-bit PWMs.
1 Channels 4 and 5 are concatenated to create one 16-bit PWM channel. Channel 4 becomes the high-order
byte and channel 5 becomes the low-order byte. Channel 5 output pin is used as the output for this 16-bit PWM
(bit 5 of port PWMP). Channel 5 clock select control bit determines the clock source, channel 5 polarity bit
determines the polarity, channel 5 enable bit enables the output and channel 5 center aligned enable bit
determines the output mode.
5
CON23
Concatenate Channels 2 and 3
0 Channels 2 and 3 are separate 8-bit PWMs.
1 Channels 2 and 3 are concatenated to create one 16-bit PWM channel. Channel 2 becomes the high-order
byte and channel 3 becomes the low-order byte. Channel 3 output pin is used as the output for this 16-bit PWM
(bit 3 of port PWMP). Channel 3 clock select control bit determines the clock source, channel 3 polarity bit
determines the polarity, channel 3 enable bit enables the output and channel 3 center aligned enable bit
determines the output mode.
4
CON01
Concatenate Channels 0 and 1
0 Channels 0 and 1 are separate 8-bit PWMs.
1 Channels 0 and 1 are concatenated to create one 16-bit PWM channel. Channel 0 becomes the high-order
byte and channel 1 becomes the low-order byte. Channel 1 output pin is used as the output for this 16-bit PWM
(bit 1 of port PWMP). Channel 1 clock select control bit determines the clock source, channel 1 polarity bit
determines the polarity, channel 1 enable bit enables the output and channel 1 center aligned enable bit
determines the output mode.
3
PSWAI
PWM Stops in Wait Mode — Enabling this bit allows for lower power consumption in wait mode by disabling the
input clock to the prescaler.
0 Allow the clock to the prescaler to continue while in wait mode.
1 Stop the input clock to the prescaler whenever the MCU is in wait mode.
2
PFRZ
PWM Counters Stop in Freeze Mode — In freeze mode, there is an option to disable the input clock to the
prescaler by setting the PFRZ bit in the PWMCTL register. If this bit is set, whenever the MCU is in freeze mode
the input clock to the prescaler is disabled. This feature is useful during emulation as it allows the PWM function
to be suspended. In this way, the counters of the PWM can be stopped while in freeze mode so that after normal
program flow is continued, the counters are re-enabled to simulate real-time operations. Because the registers
remain accessible in this mode, to re-enable the prescaler clock, either disable the PFRZ bit or exit freeze mode.
0 Allow PWM to continue while in freeze mode.
1 Disable PWM input clock to the prescaler whenever the part is in freeze mode. This is useful for emulation.
10.3.2.7
Reserved Register (PWMTST)
This register is reserved for factory testing of the PWM module and is not available in normal modes.
Module Base + 0x0006
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 10-9. Reserved Register (PWMTST)
S12P-Family Reference Manual, Rev. 1.13
342
Freescale Semiconductor
Pulse-Width Modulator (PWM8B6CV1) Block Description
Read: always read 0x0000 in normal modes
Write: unimplemented in normal modes
NOTE
Writing to this register when in special modes can alter the PWM
functionality.
10.3.2.8
Reserved Register (PWMPRSC)
This register is reserved for factory testing of the PWM module and is not available in normal modes.
Module Base + 0x0007
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 10-10. Reserved Register (PWMPRSC)
Read: always read 0x0000 in normal modes
Write: unimplemented in normal modes
NOTE
Writing to this register when in special modes can alter the PWM
functionality.
10.3.2.9
PWM Scale A Register (PWMSCLA)
PWMSCLA is the programmable scale value used in scaling clock A to generate clock SA. Clock SA is
generated by taking clock A, dividing it by the value in the PWMSCLA register and dividing that by two.
Clock SA = Clock A / (2 * PWMSCLA)
NOTE
When PWMSCLA = 0x0000, PWMSCLA value is considered a full scale
value of 256. Clock A is thus divided by 512.
Any value written to this register will cause the scale counter to load the new scale value (PWMSCLA).
Module Base + 0x0008
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-11. PWM Scale A Register (PWMSCLA)
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
343
Pulse-Width Modulator (PWM8B6CV1) Block Description
Read: anytime
Write: anytime (causes the scale counter to load the PWMSCLA value)
10.3.2.10 PWM Scale B Register (PWMSCLB)
PWMSCLB is the programmable scale value used in scaling clock B to generate clock SB. Clock SB is
generated by taking clock B, dividing it by the value in the PWMSCLB register and dividing that by two.
Clock SB = Clock B / (2 * PWMSCLB)
NOTE
When PWMSCLB = 0x0000, PWMSCLB value is considered a full scale
value of 256. Clock B is thus divided by 512.
Any value written to this register will cause the scale counter to load the new scale value (PWMSCLB).
Module Base + 0x0009
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-12. PWM Scale B Register (PWMSCLB)
Read: anytime
Write: anytime (causes the scale counter to load the PWMSCLB value).
10.3.2.11 Reserved Registers (PWMSCNTx)
The registers PWMSCNTA and PWMSCNTB are reserved for factory testing of the PWM module and
are not available in normal modes.
Module Base + 0x000A
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 10-13. Reserved Register (PWMSCNTA)
S12P-Family Reference Manual, Rev. 1.13
344
Freescale Semiconductor
Pulse-Width Modulator (PWM8B6CV1) Block Description
Module Base + 0x000B
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 10-14. Reserved Register (PWMSCNTB)
Read: always read 0x0000 in normal modes
Write: unimplemented in normal modes
NOTE
Writing to these registers when in special modes can alter the PWM
functionality.
10.3.2.12 PWM Channel Counter Registers (PWMCNTx)
Each channel has a dedicated 8-bit up/down counter which runs at the rate of the selected clock source.
The counter can be read at any time without affecting the count or the operation of the PWM channel. In
left aligned output mode, the counter counts from 0 to the value in the period register – 1. In center aligned
output mode, the counter counts from 0 up to the value in the period register and then back down to 0.
Any value written to the counter causes the counter to reset to 0x0000, the counter direction to be set to
up, the immediate load of both duty and period registers with values from the buffers, and the output to
change according to the polarity bit. The counter is also cleared at the end of the effective period (see
Section 10.4.2.5, “Left Aligned Outputs,” and Section 10.4.2.6, “Center Aligned Outputs,” for more
details). When the channel is disabled (PWMEx = 0), the PWMCNTx register does not count. When a
channel becomes enabled (PWMEx = 1), the associated PWM counter starts at the count in the
PWMCNTx register. For more detailed information on the operation of the counters, reference
Section 10.4.2.4, “PWM Timer Counters.”
In concatenated mode, writes to the 16-bit counter by using a 16-bit access or writes to either the low- or
high-order byte of the counter will reset the 16-bit counter. Reads of the 16-bit counter must be made by
16-bit access to maintain data coherency.
NOTE
Writing to the counter while the channel is enabled can cause an irregular
PWM cycle to occur.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
345
Pulse-Width Modulator (PWM8B6CV1) Block Description
Module Base + 0x000C
7
6
5
4
3
2
1
0
R
Bit 7
6
5
4
3
2
1
Bit 0
W
0
0
0
0
0
0
0
0
Reset
0
0
0
0
0
0
0
0
Figure 10-15. PWM Channel Counter Registers (PWMCNT0)
Module Base + 0x000D
7
6
5
4
3
2
1
0
R
Bit 7
6
5
4
3
2
1
Bit 0
W
0
0
0
0
0
0
0
0
Reset
0
0
0
0
0
0
0
0
Figure 10-16. PWM Channel Counter Registers (PWMCNT1)
Module Base + 0x000E
7
6
5
4
3
2
1
0
R
Bit 7
6
5
4
3
2
1
Bit 0
W
0
0
0
0
0
0
0
0
Reset
0
0
0
0
0
0
0
0
Figure 10-17. PWM Channel Counter Registers (PWMCNT2)
Module Base + 0x000F
7
6
5
4
3
2
1
0
R
Bit 7
6
5
4
3
2
1
Bit 0
W
0
0
0
0
0
0
0
0
Reset
0
0
0
0
0
0
0
0
Figure 10-18. PWM Channel Counter Registers (PWMCNT3)
Module Base + 0x00010
7
6
5
4
3
2
1
0
R
Bit 7
6
5
4
3
2
1
Bit 0
W
0
0
0
0
0
0
0
0
Reset
0
0
0
0
0
0
0
0
Figure 10-19. PWM Channel Counter Registers (PWMCNT4)
S12P-Family Reference Manual, Rev. 1.13
346
Freescale Semiconductor
Pulse-Width Modulator (PWM8B6CV1) Block Description
Module Base + 0x00011
7
6
5
4
3
2
1
0
R
Bit 7
6
5
4
3
2
1
Bit 0
W
0
0
0
0
0
0
0
0
Reset
0
0
0
0
0
0
0
0
Figure 10-20. PWM Channel Counter Registers (PWMCNT5)
Read: anytime
Write: anytime (any value written causes PWM counter to be reset to 0x0000).
10.3.2.13 PWM Channel Period Registers (PWMPERx)
There is a dedicated period register for each channel. The value in this register determines the period of
the associated PWM channel.
The period registers for each channel are double buffered so that if they change while the channel is
enabled, the change will NOT take effect until one of the following occurs:
• The effective period ends
• The counter is written (counter resets to 0x0000)
• The channel is disabled
In this way, the output of the PWM will always be either the old waveform or the new waveform, not some
variation in between. If the channel is not enabled, then writes to the period register will go directly to the
latches as well as the buffer.
NOTE
Reads of this register return the most recent value written. Reads do not
necessarily return the value of the currently active period due to the double
buffering scheme.
Reference Section 10.4.2.3, “PWM Period and Duty,” for more information.
To calculate the output period, take the selected clock source period for the channel of interest (A, B, SA,
or SB) and multiply it by the value in the period register for that channel:
• Left aligned output (CAEx = 0)
• PWMx period = channel clock period * PWMPERx center aligned output (CAEx = 1)
• PWMx period = channel clock period * (2 * PWMPERx)
For boundary case programming values, please refer to Section 10.4.2.8, “PWM Boundary Cases.”
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
347
Pulse-Width Modulator (PWM8B6CV1) Block Description
Module Base + 0x0012
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-21. PWM Channel Period Registers (PWMPER0)
Module Base + 0x0013
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-22. PWM Channel Period Registers (PWMPER1)
Module Base + 0x0014
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-23. PWM Channel Period Registers (PWMPER2)
Module Base + 0x0015
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-24. PWM Channel Period Registers (PWMPER3)
Module Base + 0x0016
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-25. PWM Channel Period Registers (PWMPER4)
S12P-Family Reference Manual, Rev. 1.13
348
Freescale Semiconductor
Pulse-Width Modulator (PWM8B6CV1) Block Description
Module Base + 0x0017
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 10-26. PWM Channel Period Registers (PWMPER5)
Read: anytime
Write: anytime
10.3.2.14 PWM Channel Duty Registers (PWMDTYx)
There is a dedicated duty register for each channel. The value in this register determines the duty of the
associated PWM channel. The duty value is compared to the counter and if it is equal to the counter value
a match occurs and the output changes state.
The duty registers for each channel are double buffered so that if they change while the channel is enabled,
the change will NOT take effect until one of the following occurs:
• The effective period ends
• The counter is written (counter resets to 0x0000)
• The channel is disabled
In this way, the output of the PWM will always be either the old duty waveform or the new duty waveform,
not some variation in between. If the channel is not enabled, then writes to the duty register will go directly
to the latches as well as the buffer.
NOTE
Reads of this register return the most recent value written. Reads do not
necessarily return the value of the currently active duty due to the double
buffering scheme.
Reference Section 10.4.2.3, “PWM Period and Duty,” for more information.
NOTE
Depending on the polarity bit, the duty registers will contain the count of
either the high time or the low time. If the polarity bit is 1, the output starts
high and then goes low when the duty count is reached, so the duty registers
contain a count of the high time. If the polarity bit is 0, the output starts low
and then goes high when the duty count is reached, so the duty registers
contain a count of the low time.
To calculate the output duty cycle (high time as a % of period) for a particular channel:
• Polarity = 0 (PPOLx = 0)
Duty cycle = [(PWMPERx PWMDTYx)/PWMPERx] * 100%
• Polarity = 1 (PPOLx = 1)
Duty cycle = [PWMDTYx / PWMPERx] * 100%
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
349
Pulse-Width Modulator (PWM8B6CV1) Block Description
•
For boundary case programming values, please refer to Section 10.4.2.8, “PWM Boundary Cases.”
Module Base + 0x0018
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
1
1
1
1
1
1
1
1
R
W
Reset
Figure 10-27. PWM Channel Duty Registers (PWMDTY0)
Module Base + 0x0019
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
1
1
1
1
1
1
1
1
R
W
Reset
Figure 10-28. PWM Channel Duty Registers (PWMDTY1)
Module Base + 0x001A
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
1
1
1
1
1
1
1
1
R
W
Reset
Figure 10-29. PWM Channel Duty Registers (PWMDTY2)
Module Base + 0x001B
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
1
1
1
1
1
1
1
1
R
W
Reset
Figure 10-30. PWM Channel Duty Registers (PWMDTY3)
Module Base + 0x001C
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
1
1
1
1
1
1
1
1
R
W
Reset
Figure 10-31. PWM Channel Duty Registers (PWMDTY4)
S12P-Family Reference Manual, Rev. 1.13
350
Freescale Semiconductor
Pulse-Width Modulator (PWM8B6CV1) Block Description
Module Base + 0x001D
7
6
5
4
3
2
1
0
Bit 7
6
5
4
3
2
1
Bit 0
1
1
1
1
1
1
1
1
R
W
Reset
Figure 10-32. PWM Channel Duty Registers (PWMDTY5)
Read: anytime
Write: anytime
10.3.2.15 PWM Shutdown Register (PWMSDN)
The PWMSDN register provides for the shutdown functionality of the PWM module in the emergency
cases.
Module Base + 0x00E
7
6
5
PWMIF
PWMIE
R
0
W
Reset
4
3
2
0
PWM5IN
PWMLVL
1
0
PWM5INL
PWM5ENA
0
0
PWMRSTRT
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 10-33. PWM Shutdown Register (PWMSDN)
Read: anytime
Write: anytime
Table 10-10. PWMSDN Field Descriptions
Field
Description
7
PWMIF
PWM Interrupt Flag — Any change from passive to asserted (active) state or from active to passive state will be
flagged by setting the PWMIF flag = 1. The flag is cleared by writing a logic 1 to it. Writing a 0 has no effect.
0 No change on PWM5IN input.
1 Change on PWM5IN input
6
PWMIE
PWM Interrupt Enable — If interrupt is enabled an interrupt to the CPU is asserted.
0 PWM interrupt is disabled.
1 PWM interrupt is enabled.
5
PWM Restart — The PWM can only be restarted if the PWM channel input 5 is deasserted. After writing a logic 1
PWMRSTRT to the PWMRSTRT bit (trigger event) the PWM channels start running after the corresponding counter passes
next “counter = 0” phase.
Also, if the PWM5ENA bit is reset to 0, the PWM do not start before the counter passes 0x0000.
The bit is always read as 0.
4
PWMLVL
PWM Shutdown Output Level — If active level as defined by the PWM5IN input, gets asserted all enabled PWM
channels are immediately driven to the level defined by PWMLVL.
0 PWM outputs are forced to 0
1 PWM outputs are forced to 1.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
Table 10-10. PWMSDN Field Descriptions (continued)
Field
Description
2
PWM5IN
PWM Channel 5 Input Status — This reflects the current status of the PWM5 pin.
1
PWM5INL
PWM Shutdown Active Input Level for Channel 5 — If the emergency shutdown feature is enabled
(PWM5ENA = 1), this bit determines the active level of the PWM5 channel.
0 Active level is low
1 Active level is high
0
PWM Emergency Shutdown Enable — If this bit is logic 1 the pin associated with channel 5 is forced to input
PWM5ENA and the emergency shutdown feature is enabled. All the other bits in this register are meaningful only if
PWM5ENA = 1.
0 PWM emergency feature disabled.
1 PWM emergency feature is enabled.
10.4
Functional Description
10.4.1
PWM Clock Select
There are four available clocks called clock A, clock B, clock SA (scaled A), and clock SB (scaled B).
These four clocks are based on the bus clock.
Clock A and B can be software selected to be 1, 1/2, 1/4, 1/8,..., 1/64, 1/128 times the bus clock. Clock SA
uses clock A as an input and divides it further with a reloadable counter. Similarly, clock SB uses clock B
as an input and divides it further with a reloadable counter. The rates available for clock SA are software
selectable to be clock A divided by 2, 4, 6, 8, ..., or 512 in increments of divide by 2. Similar rates are
available for clock SB. Each PWM channel has the capability of selecting one of two clocks, either the
pre-scaled clock (clock A or B) or the scaled clock (clock SA or SB).
The block diagram in Figure 10-34 shows the four different clocks and how the scaled clocks are created.
10.4.1.1
Prescale
The input clock to the PWM prescaler is the bus clock. It can be disabled whenever the part is in freeze
mode by setting the PFRZ bit in the PWMCTL register. If this bit is set, whenever the MCU is in freeze
mode the input clock to the prescaler is disabled. This is useful for emulation in order to freeze the PWM.
The input clock can also be disabled when all six PWM channels are disabled (PWME5–PWME0 = 0)
This is useful for reducing power by disabling the prescale counter.
Clock A and clock B are scaled values of the input clock. The value is software selectable for both clock A
and clock B and has options of 1, 1/2, 1/4, 1/8, 1/16, 1/32, 1/64, or 1/128 times the bus clock. The value
selected for clock A is determined by the PCKA2, PCKA1, and PCKA0 bits in the PWMPRCLK register.
The value selected for clock B is determined by the PCKB2, PCKB1, and PCKB0 bits also in the
PWMPRCLK register.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
Clock A
M
U
X
Clock to
PWM Ch 0
Clock A/2, A/4, A/6,....A/512
PCKA2
PCKA1
PCKA0
PCLK0
8-Bit Down Counter
Count = 1
M
U
X
Load
PWMSCLA
DIV 2
Clock SA
PCLK1
M
U
X
M
Clock to
PWM Ch 1
Clock to
PWM Ch 2
U
PCLK2
8 16 32 64 128
M
U
X
Clock B
4
M
U
X
Clock to
PWM Ch 4
Clock B/2, B/4, B/6,....B/512
PCLK4
M
U
8-Bit Down Counter
X
Count = 1
M
U
X
Load
PWMSCLB
Clock SB
PCLK5
PCKB2
PCKB1
PCKB0
DIV 2
Clock to
PWM Ch 5
PWME5:0
Bus Clock
PFRZ
FREEZE
Clock to
PWM Ch 3
PCLK3
2
Divide by Prescaler Taps:
X
PRESCALE
SCALE
CLOCK SELECT
Figure 10-34. PWM Clock Select Block Diagram
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Pulse-Width Modulator (PWM8B6CV1) Block Description
10.4.1.2
Clock Scale
The scaled A clock uses clock A as an input and divides it further with a user programmable value and
then divides this by 2. The scaled B clock uses clock B as an input and divides it further with a user
programmable value and then divides this by 2. The rates available for clock SA are software selectable
to be clock A divided by 2, 4, 6, 8, ..., or 512 in increments of divide by 2. Similar rates are available for
clock SB.
Clock A is used as an input to an 8-bit down counter. This down counter loads a user programmable scale
value from the scale register (PWMSCLA). When the down counter reaches 1, two things happen; a pulse
is output and the 8-bit counter is re-loaded. The output signal from this circuit is further divided by two.
This gives a greater range with only a slight reduction in granularity. Clock SA equals clock A divided by
two times the value in the PWMSCLA register.
NOTE
Clock SA = Clock A / (2 * PWMSCLA)
When PWMSCLA = 0x0000, PWMSCLA value is considered a full scale
value of 256. Clock A is thus divided by 512.
Similarly, clock B is used as an input to an 8-bit down counter followed by a divide by two producing clock
SB. Thus, clock SB equals clock B divided by two times the value in the PWMSCLB register.
NOTE
Clock SB = Clock B / (2 * PWMSCLB)
When PWMSCLB = 0x0000, PWMSCLB value is considered a full scale
value of 256. Clock B is thus divided by 512.
As an example, consider the case in which the user writes 0x00FF into the PWMSCLA register. Clock A
for this case will be bus clock divided by 4. A pulse will occur at a rate of once every 255 x 4 bus cycles.
Passing this through the divide by two circuit produces a clock signal at a bus clock divided by 2040 rate.
Similarly, a value of 0x0001 in the PWMSCLA register when clock A is bus clock divided by 4 will
produce a bus clock divided by 8 rate.
Writing to PWMSCLA or PWMSCLB causes the associated 8-bit down counter to be re-loaded.
Otherwise, when changing rates the counter would have to count down to 0x0001 before counting at the
proper rate. Forcing the associated counter to re-load the scale register value every time PWMSCLA or
PWMSCLB is written prevents this.
NOTE
Writing to the scale registers while channels are operating can cause
irregularities in the PWM outputs.
10.4.1.3
Clock Select
Each PWM channel has the capability of selecting one of two clocks. For channels 0, 1, 4, and 5 the clock
choices are clock A or clock SA. For channels 2 and 3 the choices are clock B or clock SB. The clock
selection is done with the PCLKx control bits in the PWMCLK register.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
NOTE
Changing clock control bits while channels are operating can cause
irregularities in the PWM outputs.
10.4.2
PWM Channel Timers
The main part of the PWM module are the actual timers. Each of the timer channels has a counter, a period
register and a duty register (each are 8 bit). The waveform output period is controlled by a match between
the period register and the value in the counter. The duty is controlled by a match between the duty register
and the counter value and causes the state of the output to change during the period. The starting polarity
of the output is also selectable on a per channel basis. Figure 10-35 shows a block diagram for PWM timer.
Clock Source
From Port PWMP
Data Register
8-Bit Counter
GATE
PWMCNTx
(clock edge sync)
8-Bit Compare =
up/down reset
T
Q
PWMDTYx
Q
M
U
X
R
M
U
X
To Pin
Driver
8-Bit Compare =
PWMPERx
PPOLx
Q
T
CAEx
Q
R
PWMEx
Figure 10-35. PWM Timer Channel Block Diagram
10.4.2.1
PWM Enable
Each PWM channel has an enable bit (PWMEx) to start its waveform output. When any of the PWMEx
bits are set (PWMEx = 1), the associated PWM output signal is enabled immediately. However, the actual
PWM waveform is not available on the associated PWM output until its clock source begins its next cycle
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Pulse-Width Modulator (PWM8B6CV1) Block Description
due to the synchronization of PWMEx and the clock source. An exception to this is when channels are
concatenated. Refer to Section 10.4.2.7, “PWM 16-Bit Functions,” for more detail.
NOTE
The first PWM cycle after enabling the channel can be irregular.
On the front end of the PWM timer, the clock is enabled to the PWM circuit by the PWMEx bit being high.
There is an edge-synchronizing circuit to guarantee that the clock will only be enabled or disabled at an
edge. When the channel is disabled (PWMEx = 0), the counter for the channel does not count.
10.4.2.2
PWM Polarity
Each channel has a polarity bit to allow starting a waveform cycle with a high or low signal. This is shown
on the block diagram as a mux select of either the Q output or the Q output of the PWM output flip-flop.
When one of the bits in the PWMPOL register is set, the associated PWM channel output is high at the
beginning of the waveform, then goes low when the duty count is reached. Conversely, if the polarity bit
is 0, the output starts low and then goes high when the duty count is reached.
10.4.2.3
PWM Period and Duty
Dedicated period and duty registers exist for each channel and are double buffered so that if they change
while the channel is enabled, the change will NOT take effect until one of the following occurs:
• The effective period ends
• The counter is written (counter resets to 0x0000)
• The channel is disabled
In this way, the output of the PWM will always be either the old waveform or the new waveform, not some
variation in between. If the channel is not enabled, then writes to the period and duty registers will go
directly to the latches as well as the buffer.
A change in duty or period can be forced into effect “immediately” by writing the new value to the duty
and/or period registers and then writing to the counter. This forces the counter to reset and the new duty
and/or period values to be latched. In addition, because the counter is readable it is possible to know where
the count is with respect to the duty value and software can be used to make adjustments.
NOTE
When forcing a new period or duty into effect immediately, an irregular
PWM cycle can occur.
Depending on the polarity bit, the duty registers will contain the count of
either the high time or the low time.
10.4.2.4
PWM Timer Counters
Each channel has a dedicated 8-bit up/down counter which runs at the rate of the selected clock source
(reference Figure 10-34 for the available clock sources and rates). The counter compares to two registers,
a duty register and a period register as shown in Figure 10-35. When the PWM counter matches the duty
register the output flip-flop changes state causing the PWM waveform to also change state. A match
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Pulse-Width Modulator (PWM8B6CV1) Block Description
between the PWM counter and the period register behaves differently depending on what output mode is
selected as shown in Figure 10-35 and described in Section 10.4.2.5, “Left Aligned Outputs,” and
Section 10.4.2.6, “Center Aligned Outputs.”
Each channel counter can be read at anytime without affecting the count or the operation of the PWM
channel.
Any value written to the counter causes the counter to reset to 0x0000, the counter direction to be set to
up, the immediate load of both duty and period registers with values from the buffers, and the output to
change according to the polarity bit. When the channel is disabled (PWMEx = 0), the counter stops. When
a channel becomes enabled (PWMEx = 1), the associated PWM counter continues from the count in the
PWMCNTx register. This allows the waveform to resume when the channel is re-enabled. When the
channel is disabled, writing 0 to the period register will cause the counter to reset on the next selected
clock.
NOTE
If the user wants to start a new “clean” PWM waveform without any
“history” from the old waveform, the user must write to channel counter
(PWMCNTx) prior to enabling the PWM channel (PWMEx = 1).
Generally, writes to the counter are done prior to enabling a channel to start from a known state. However,
writing a counter can also be done while the PWM channel is enabled (counting). The effect is similar to
writing the counter when the channel is disabled except that the new period is started immediately with
the output set according to the polarity bit.
NOTE
Writing to the counter while the channel is enabled can cause an irregular
PWM cycle to occur.
The counter is cleared at the end of the effective period (see Section 10.4.2.5, “Left Aligned Outputs,” and
Section 10.4.2.6, “Center Aligned Outputs,” for more details).
Table 10-11. PWM Timer Counter Conditions
Counter Clears (0x0000)
When PWMCNTx register
written to any value
Effective period ends
10.4.2.5
Counter Counts
When PWM channel is
enabled (PWMEx = 1). Counts
from last value in PWMCNTx.
Counter Stops
When PWM channel is
disabled (PWMEx = 0)
Left Aligned Outputs
The PWM timer provides the choice of two types of outputs, left aligned or center aligned outputs. They
are selected with the CAEx bits in the PWMCAE register. If the CAEx bit is cleared (CAEx = 0), the
corresponding PWM output will be left aligned.
In left aligned output mode, the 8-bit counter is configured as an up counter only. It compares to two
registers, a duty register and a period register as shown in the block diagram in Figure 10-35. When the
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Pulse-Width Modulator (PWM8B6CV1) Block Description
PWM counter matches the duty register the output flip-flop changes state causing the PWM waveform to
also change state. A match between the PWM counter and the period register resets the counter and the
output flip-flop as shown in Figure 10-35 as well as performing a load from the double buffer period and
duty register to the associated registers as described in Section 10.4.2.3, “PWM Period and Duty.” The
counter counts from 0 to the value in the period register – 1.
NOTE
Changing the PWM output mode from left aligned output to center aligned
output (or vice versa) while channels are operating can cause irregularities
in the PWM output. It is recommended to program the output mode before
enabling the PWM channel.
PPOLx = 0
PPOLx = 1
PWMDTYx
Period = PWMPERx
Figure 10-36. PWM Left Aligned Output Waveform
To calculate the output frequency in left aligned output mode for a particular channel, take the selected
clock source frequency for the channel (A, B, SA, or SB) and divide it by the value in the period register
for that channel.
• PWMx frequency = clock (A, B, SA, or SB) / PWMPERx
• PWMx duty cycle (high time as a% of period):
— Polarity = 0 (PPOLx = 0)
Duty cycle = [(PWMPERx-PWMDTYx)/PWMPERx] * 100%
— Polarity = 1 (PPOLx = 1)
Duty cycle = [PWMDTYx / PWMPERx] * 100%
As an example of a left aligned output, consider the following case:
Clock source = bus clock, where bus clock = 10 MHz (100 ns period)
PPOLx = 0
PWMPERx = 4
PWMDTYx = 1
PWMx frequency = 10 MHz/4 = 2.5 MHz
PWMx period = 400 ns
PWMx duty cycle = 3/4 *100% = 75%
Shown below is the output waveform generated.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
E = 100 ns
DUTY CYCLE = 75%
PERIOD = 400 ns
Figure 10-37. PWM Left Aligned Output Example Waveform
10.4.2.6
Center Aligned Outputs
For center aligned output mode selection, set the CAEx bit (CAEx = 1) in the PWMCAE register and the
corresponding PWM output will be center aligned.
The 8-bit counter operates as an up/down counter in this mode and is set to up whenever the counter is
equal to 0x0000. The counter compares to two registers, a duty register and a period register as shown in
the block diagram in Figure 10-35. When the PWM counter matches the duty register the output flip-flop
changes state causing the PWM waveform to also change state. A match between the PWM counter and
the period register changes the counter direction from an up-count to a down-count. When the PWM
counter decrements and matches the duty register again, the output flip-flop changes state causing the
PWM output to also change state. When the PWM counter decrements and reaches 0, the counter direction
changes from a down-count back to an up-count and a load from the double buffer period and duty
registers to the associated registers is performed as described in Section 10.4.2.3, “PWM Period and
Duty.” The counter counts from 0 up to the value in the period register and then back down to 0. Thus the
effective period is PWMPERx*2.
NOTE
Changing the PWM output mode from left aligned output to center aligned
output (or vice versa) while channels are operating can cause irregularities
in the PWM output. It is recommended to program the output mode before
enabling the PWM channel.
PPOLx = 0
PPOLx = 1
PWMDTYx
PWMDTYx
PWMPERx
PWMPERx
Period = PWMPERx*2
Figure 10-38. PWM Center Aligned Output Waveform
To calculate the output frequency in center aligned output mode for a particular channel, take the selected
clock source frequency for the channel (A, B, SA, or SB) and divide it by twice the value in the period
register for that channel.
• PWMx frequency = clock (A, B, SA, or SB) / (2*PWMPERx)
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Pulse-Width Modulator (PWM8B6CV1) Block Description
•
PWMx duty cycle (high time as a% of period):
— Polarity = 0 (PPOLx = 0)
Duty cycle = [(PWMPERx-PWMDTYx)/PWMPERx] * 100%
— Polarity = 1 (PPOLx = 1)
Duty cycle = [PWMDTYx / PWMPERx] * 100%
As an example of a center aligned output, consider the following case:
Clock source = bus clock, where bus clock = 10 MHz (100 ns period)
PPOLx = 0
PWMPERx = 4
PWMDTYx = 1
PWMx frequency = 10 MHz/8 = 1.25 MHz
PWMx period = 800 ns
PWMx duty cycle = 3/4 *100% = 75%
Shown below is the output waveform generated.
E = 100 ns
E = 100 ns
DUTY CYCLE = 75%
PERIOD = 800 ns
Figure 10-39. PWM Center Aligned Output Example Waveform
10.4.2.7
PWM 16-Bit Functions
The PWM timer also has the option of generating 6-channels of 8-bits or 3-channels of 16-bits for greater
PWM resolution}. This 16-bit channel option is achieved through the concatenation of two 8-bit channels.
The PWMCTL register contains three control bits, each of which is used to concatenate a pair of PWM
channels into one 16-bit channel. Channels 4 and 5 are concatenated with the CON45 bit, channels 2 and 3
are concatenated with the CON23 bit, and channels 0 and 1 are concatenated with the CON01 bit.
NOTE
Change these bits only when both corresponding channels are disabled.
When channels 4 and 5 are concatenated, channel 4 registers become the high-order bytes of the double
byte channel as shown in Figure 10-40. Similarly, when channels 2 and 3 are concatenated, channel 2
registers become the high-order bytes of the double byte channel. When channels 0 and 1 are concatenated,
channel 0 registers become the high-order bytes of the double byte channel.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
Clock Source 5
High
Low
PWMCNT4
PWCNT5
Period/Duty Compare
PWM5
Clock Source 3
High
Low
PWMCNT2
PWCNT3
Period/Duty Compare
PWM3
Clock Source 1
High
Low
PWMCNT0
PWCNT1
Period/Duty Compare
PWM1
Figure 10-40. PWM 16-Bit Mode
When using the 16-bit concatenated mode, the clock source is determined by the low-order 8-bit channel
clock select control bits. That is channel 5 when channels 4 and 5 are concatenated, channel 3 when
channels 2 and 3 are concatenated, and channel 1 when channels 0 and 1 are concatenated. The resulting
PWM is output to the pins of the corresponding low-order 8-bit channel as also shown in Figure 10-40.
The polarity of the resulting PWM output is controlled by the PPOLx bit of the corresponding low-order
8-bit channel as well.
After concatenated mode is enabled (CONxx bits set in PWMCTL register), enabling/disabling the
corresponding 16-bit PWM channel is controlled by the low-order PWMEx bit. In this case, the high-order
bytes PWMEx bits have no effect and their corresponding PWM output is disabled.
In concatenated mode, writes to the 16-bit counter by using a 16-bit access or writes to either the low or
high-order byte of the counter will reset the 16-bit counter. Reads of the 16-bit counter must be made by
16-bit access to maintain data coherency.
Either left aligned or center aligned output mode can be used in concatenated mode and is controlled by
the low-order CAEx bit. The high-order CAEx bit has no effect.
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Pulse-Width Modulator (PWM8B6CV1) Block Description
Table 10-12 is used to summarize which channels are used to set the various control bits when in 16-bit
mode.
Table 10-12. 16-bit Concatenation Mode Summary
10.4.2.8
CONxx
PWMEx
PPOLx
PCLKx
CAEx
PWMx Output
CON45
PWME5
PPOL5
PCLK5
CAE5
PWM5
CON23
PWME3
PPOL3
PCLK3
CAE3
PWM3
CON01
PWME1
PPOL1
PCLK1
CAE1
PWM1
PWM Boundary Cases
Table 10-13 summarizes the boundary conditions for the PWM regardless of the output mode (left aligned
or center aligned) and 8-bit (normal) or 16-bit (concatenation):
Table 10-13. PWM Boundary Cases
PWMDTYx
PWMPERx
PPOLx
PWMx Output
0x0000
(indicates no duty)
>0x0000
1
Always Low
0x0000
(indicates no duty)
>0x0000
0
Always High
XX
0x0000(1)
(indicates no period)
1
Always High
XX
0x00001
(indicates no period)
0
Always Low
>= PWMPERx
XX
1
Always High
>= PWMPERx
XX
0
Always Low
1. Counter = 0x0000 and does not count.
10.5
Resets
The reset state of each individual bit is listed within the register description section (see Section 10.3,
“Memory Map and Register Definition,” which details the registers and their bit-fields. All special
functions or modes which are initialized during or just following reset are described within this section.
• The 8-bit up/down counter is configured as an up counter out of reset.
• All the channels are disabled and all the counters don’t count.
10.6
Interrupts
The PWM8B6CV1 module has only one interrupt which is generated at the time of emergency shutdown,
if the corresponding enable bit (PWMIE) is set. This bit is the enable for the interrupt. The interrupt flag
PWMIF is set whenever the input level of the PWM5 channel changes while PWM5ENA=1 or when
PWMENA is being asserted while the level at PWM5 is active.
A description of the registers involved and affected due to this interrupt is explained in Section 10.3.2.15,
“PWM Shutdown Register (PWMSDN).”
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Chapter 11
Serial Communication Interface (S12SCIV5)
Table 11-1. Revision History
Version
Number
Revision
Date
05.01
04/16/2004
05.02
10/14/2005
05.03
12/25/2008
05.04
08/05/2009
11.1
Effective
Date
Author
Description of Changes
Update OR and PF flag description; Correct baud rate
tolerance in 4.7.5.1 and 4.7.5.2; Clean up classification and
NDA message banners
Correct alternative registers address;
Remove unavailable baud rate in Table1-16
remove redundancy comments in Figure1-2
fix typo, SCIBDL reset value be 0x04, not 0x00
Introduction
This block guide provides an overview of the serial communication interface (SCI) module.
The SCI allows asynchronous serial communications with peripheral devices and other CPUs.
11.1.1
Glossary
IR: InfraRed
IrDA: Infrared Design Associate
IRQ: Interrupt Request
LIN: Local Interconnect Network
LSB: Least Significant Bit
MSB: Most Significant Bit
NRZ: Non-Return-to-Zero
RZI: Return-to-Zero-Inverted
RXD: Receive Pin
SCI : Serial Communication Interface
TXD: Transmit Pin
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Serial Communication Interface (S12SCIV5)
11.1.2
Features
The SCI includes these distinctive features:
• Full-duplex or single-wire operation
• Standard mark/space non-return-to-zero (NRZ) format
• Selectable IrDA 1.4 return-to-zero-inverted (RZI) format with programmable pulse widths
• 13-bit baud rate selection
• Programmable 8-bit or 9-bit data format
• Separately enabled transmitter and receiver
• Programmable polarity for transmitter and receiver
• Programmable transmitter output parity
• Two receiver wakeup methods:
— Idle line wakeup
— Address mark wakeup
• Interrupt-driven operation with eight flags:
— Transmitter empty
— Transmission complete
— Receiver full
— Idle receiver input
— Receiver overrun
— Noise error
— Framing error
— Parity error
— Receive wakeup on active edge
— Transmit collision detect supporting LIN
— Break Detect supporting LIN
• Receiver framing error detection
• Hardware parity checking
• 1/16 bit-time noise detection
11.1.3
Modes of Operation
The SCI functions the same in normal, special, and emulation modes. It has two low power modes, wait
and stop modes.
• Run mode
• Wait mode
• Stop mode
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Serial Communication Interface (S12SCIV5)
11.1.4
Block Diagram
Figure 11-1 is a high level block diagram of the SCI module, showing the interaction of various function
blocks.
SCI Data Register
RXD Data In
Infrared
Decoder
Receive Shift Register
Receive & Wakeup
Control
Bus Clock
Baud Rate
Generator
IDLE
Receive
RDRF/OR
Interrupt
Generation BRKD
RXEDG
BERR
Data Format Control
Transmit Control
1/16
Transmit Shift Register
SCI
Interrupt
Request
Transmit
TDRE
Interrupt
Generation TC
Infrared
Encoder
Data Out TXD
SCI Data Register
Figure 11-1. SCI Block Diagram
11.2
External Signal Description
The SCI module has a total of two external pins.
11.2.1
TXD — Transmit Pin
The TXD pin transmits SCI (standard or infrared) data. It will idle high in either mode and is high
impedance anytime the transmitter is disabled.
11.2.2
RXD — Receive Pin
The RXD pin receives SCI (standard or infrared) data. An idle line is detected as a line high. This input is
ignored when the receiver is disabled and should be terminated to a known voltage.
11.3
Memory Map and Register Definition
This section provides a detailed description of all the SCI registers.
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Serial Communication Interface (S12SCIV5)
11.3.1
Module Memory Map and Register Definition
The memory map for the SCI module is given below in Figure 11-2. The address listed for each register is
the address offset. The total address for each register is the sum of the base address for the SCI module and
the address offset for each register.
11.3.2
Register Descriptions
This section consists of register descriptions in address order. Each description includes a standard register
diagram with an associated figure number. Writes to a reserved register locations do not have any effect
and reads of these locations return a zero. Details of register bit and field function follow the register
diagrams, in bit order.
Register
Name
0x0000
SCIBDH1
0x0001
SCIBDL1
0x0002
SCICR11
0x0000
SCIASR12
0x0001
SCIACR12
R
W
R
W
R
W
R
W
R
W
0x0002
SCIACR22
W
0x0003
SCICR2
W
0x0004
SCISR1
0x0005
SCISR2
R
R
R
Bit 7
6
5
4
3
2
1
Bit 0
IREN
TNP1
TNP0
SBR12
SBR11
SBR10
SBR9
SBR8
SBR7
SBR6
SBR5
SBR4
SBR3
SBR2
SBR1
SBR0
LOOPS
SCISWAI
RSRC
M
WAKE
ILT
PE
PT
0
0
0
0
BERRV
BERRIF
BKDIF
0
0
0
0
BERRIE
BKDIE
0
0
0
0
0
BERRM1
BERRM0
BKDFE
TIE
TCIE
RIE
ILIE
TE
RE
RWU
SBK
TDRE
TC
RDRF
IDLE
OR
NF
FE
PF
0
0
TXPOL
RXPOL
BRK13
TXDIR
RXEDGIF
RXEDGIE
0
W
R
W
AMAP
RAF
= Unimplemented or Reserved
Figure 11-2. SCI Register Summary (Sheet 1 of 2)
S12P-Family Reference Manual, Rev. 1.13
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Freescale Semiconductor
Serial Communication Interface (S12SCIV5)
Register
Name
Bit 7
R
6
R8
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0x0006
SCIDRH
W
0x0007
SCIDRL
R
R7
R6
R5
R4
R3
R2
R1
R0
W
T7
T6
T5
T4
T3
T2
T1
T0
T8
1.These registers are accessible if the AMAP bit in the SCISR2 register is set to zero.
2,These registers are accessible if the AMAP bit in the SCISR2 register is set to one.
= Unimplemented or Reserved
Figure 11-2. SCI Register Summary (Sheet 2 of 2)
11.3.2.1
SCI Baud Rate Registers (SCIBDH, SCIBDL)
Module Base + 0x0000
R
W
Reset
7
6
5
4
3
2
1
0
IREN
TNP1
TNP0
SBR12
SBR11
SBR10
SBR9
SBR8
0
0
0
0
0
0
0
0
Figure 11-3. SCI Baud Rate Register (SCIBDH)
Module Base + 0x0001
R
W
Reset
7
6
5
4
3
2
1
0
SBR7
SBR6
SBR5
SBR4
SBR3
SBR2
SBR1
SBR0
0
0
0
0
0
1
0
0
Figure 11-4. SCI Baud Rate Register (SCIBDL)
Read: Anytime, if AMAP = 0. If only SCIBDH is written to, a read will not return the correct data until
SCIBDL is written to as well, following a write to SCIBDH.
Write: Anytime, if AMAP = 0.
NOTE
Those two registers are only visible in the memory map if AMAP = 0 (reset
condition).
The SCI baud rate register is used by to determine the baud rate of the SCI, and to control the infrared
modulation/demodulation submodule.
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Serial Communication Interface (S12SCIV5)
Table 11-2. SCIBDH and SCIBDL Field Descriptions
Field
7
IREN
Description
Infrared Enable Bit — This bit enables/disables the infrared modulation/demodulation submodule.
0 IR disabled
1 IR enabled
6:5
TNP[1:0]
Transmitter Narrow Pulse Bits — These bits enable whether the SCI transmits a 1/16, 3/16, 1/32 or 1/4 narrow
pulse. See Table 11-3.
4:0
7:0
SBR[12:0]
SCI Baud Rate Bits — The baud rate for the SCI is determined by the bits in this register. The baud rate is
calculated two different ways depending on the state of the IREN bit.
The formulas for calculating the baud rate are:
When IREN = 0 then,
SCI baud rate = SCI bus clock / (16 x SBR[12:0])
When IREN = 1 then,
SCI baud rate = SCI bus clock / (32 x SBR[12:1])
Note: The baud rate generator is disabled after reset and not started until the TE bit or the RE bit is set for the
first time. The baud rate generator is disabled when (SBR[12:0] = 0 and IREN = 0) or (SBR[12:1] = 0 and
IREN = 1).
Note: Writing to SCIBDH has no effect without writing to SCIBDL, because writing to SCIBDH puts the data in
a temporary location until SCIBDL is written to.
Table 11-3. IRSCI Transmit Pulse Width
TNP[1:0]
11.3.2.2
Narrow Pulse Width
11
1/4
10
1/32
01
1/16
00
3/16
SCI Control Register 1 (SCICR1)
Module Base + 0x0002
R
W
Reset
7
6
5
4
3
2
1
0
LOOPS
SCISWAI
RSRC
M
WAKE
ILT
PE
PT
0
0
0
0
0
0
0
0
Figure 11-5. SCI Control Register 1 (SCICR1)
Read: Anytime, if AMAP = 0.
Write: Anytime, if AMAP = 0.
NOTE
This register is only visible in the memory map if AMAP = 0 (reset
condition).
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Serial Communication Interface (S12SCIV5)
Table 11-4. SCICR1 Field Descriptions
Field
Description
7
LOOPS
Loop Select Bit — LOOPS enables loop operation. In loop operation, the RXD pin is disconnected from the SCI
and the transmitter output is internally connected to the receiver input. Both the transmitter and the receiver must
be enabled to use the loop function.
0 Normal operation enabled
1 Loop operation enabled
The receiver input is determined by the RSRC bit.
6
SCISWAI
5
RSRC
4
M
SCI Stop in Wait Mode Bit — SCISWAI disables the SCI in wait mode.
0 SCI enabled in wait mode
1 SCI disabled in wait mode
Receiver Source Bit — When LOOPS = 1, the RSRC bit determines the source for the receiver shift register
input. See Table 11-5.
0 Receiver input internally connected to transmitter output
1 Receiver input connected externally to transmitter
Data Format Mode Bit — MODE determines whether data characters are eight or nine bits long.
0 One start bit, eight data bits, one stop bit
1 One start bit, nine data bits, one stop bit
3
WAKE
Wakeup Condition Bit — WAKE determines which condition wakes up the SCI: a logic 1 (address mark) in the
most significant bit position of a received data character or an idle condition on the RXD pin.
0 Idle line wakeup
1 Address mark wakeup
2
ILT
Idle Line Type Bit — ILT determines when the receiver starts counting logic 1s as idle character bits. The
counting begins either after the start bit or after the stop bit. If the count begins after the start bit, then a string of
logic 1s preceding the stop bit may cause false recognition of an idle character. Beginning the count after the
stop bit avoids false idle character recognition, but requires properly synchronized transmissions.
0 Idle character bit count begins after start bit
1 Idle character bit count begins after stop bit
1
PE
Parity Enable Bit — PE enables the parity function. When enabled, the parity function inserts a parity bit in the
most significant bit position.
0 Parity function disabled
1 Parity function enabled
0
PT
Parity Type Bit — PT determines whether the SCI generates and checks for even parity or odd parity. With even
parity, an even number of 1s clears the parity bit and an odd number of 1s sets the parity bit. With odd parity, an
odd number of 1s clears the parity bit and an even number of 1s sets the parity bit.
1 Even parity
1 Odd parity
Table 11-5. Loop Functions
LOOPS
RSRC
Function
0
x
Normal operation
1
0
Loop mode with transmitter output internally connected to receiver input
1
1
Single-wire mode with TXD pin connected to receiver input
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Serial Communication Interface (S12SCIV5)
11.3.2.3
SCI Alternative Status Register 1 (SCIASR1)
Module Base + 0x0000
7
R
W
Reset
RXEDGIF
0
6
5
4
3
2
0
0
0
0
BERRV
0
0
0
0
0
1
0
BERRIF
BKDIF
0
0
= Unimplemented or Reserved
Figure 11-6. SCI Alternative Status Register 1 (SCIASR1)
Read: Anytime, if AMAP = 1
Write: Anytime, if AMAP = 1
Table 11-6. SCIASR1 Field Descriptions
Field
7
RXEDGIF
Description
Receive Input Active Edge Interrupt Flag — RXEDGIF is asserted, if an active edge (falling if RXPOL = 0,
rising if RXPOL = 1) on the RXD input occurs. RXEDGIF bit is cleared by writing a “1” to it.
0 No active receive on the receive input has occurred
1 An active edge on the receive input has occurred
2
BERRV
Bit Error Value — BERRV reflects the state of the RXD input when the bit error detect circuitry is enabled and
a mismatch to the expected value happened. The value is only meaningful, if BERRIF = 1.
0 A low input was sampled, when a high was expected
1 A high input reassembled, when a low was expected
1
BERRIF
Bit Error Interrupt Flag — BERRIF is asserted, when the bit error detect circuitry is enabled and if the value
sampled at the RXD input does not match the transmitted value. If the BERRIE interrupt enable bit is set an
interrupt will be generated. The BERRIF bit is cleared by writing a “1” to it.
0 No mismatch detected
1 A mismatch has occurred
0
BKDIF
11.3.2.4
Break Detect Interrupt Flag — BKDIF is asserted, if the break detect circuitry is enabled and a break signal is
received. If the BKDIE interrupt enable bit is set an interrupt will be generated. The BKDIF bit is cleared by writing
a “1” to it.
0 No break signal was received
1 A break signal was received
SCI Alternative Control Register 1 (SCIACR1)
Module Base + 0x0001
7
R
W
Reset
RXEDGIE
0
6
5
4
3
2
0
0
0
0
0
0
0
0
0
0
1
0
BERRIE
BKDIE
0
0
= Unimplemented or Reserved
Figure 11-7. SCI Alternative Control Register 1 (SCIACR1)
Read: Anytime, if AMAP = 1
Write: Anytime, if AMAP = 1
S12P-Family Reference Manual, Rev. 1.13
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Freescale Semiconductor
Serial Communication Interface (S12SCIV5)
Table 11-7. SCIACR1 Field Descriptions
Field
Description
7
RSEDGIE
Receive Input Active Edge Interrupt Enable — RXEDGIE enables the receive input active edge interrupt flag,
RXEDGIF, to generate interrupt requests.
0 RXEDGIF interrupt requests disabled
1 RXEDGIF interrupt requests enabled
1
BERRIE
0
BKDIE
11.3.2.5
Bit Error Interrupt Enable — BERRIE enables the bit error interrupt flag, BERRIF, to generate interrupt
requests.
0 BERRIF interrupt requests disabled
1 BERRIF interrupt requests enabled
Break Detect Interrupt Enable — BKDIE enables the break detect interrupt flag, BKDIF, to generate interrupt
requests.
0 BKDIF interrupt requests disabled
1 BKDIF interrupt requests enabled
SCI Alternative Control Register 2 (SCIACR2)
Module Base + 0x0002
R
7
6
5
4
3
0
0
0
0
0
0
0
0
0
0
W
Reset
2
1
0
BERRM1
BERRM0
BKDFE
0
0
0
= Unimplemented or Reserved
Figure 11-8. SCI Alternative Control Register 2 (SCIACR2)
Read: Anytime, if AMAP = 1
Write: Anytime, if AMAP = 1
Table 11-8. SCIACR2 Field Descriptions
Field
Description
2:1
Bit Error Mode — Those two bits determines the functionality of the bit error detect feature. See Table 11-9.
BERRM[1:0]
0
BKDFE
Break Detect Feature Enable — BKDFE enables the break detect circuitry.
0 Break detect circuit disabled
1 Break detect circuit enabled
Table 11-9. Bit Error Mode Coding
BERRM1
BERRM0
Function
0
0
Bit error detect circuit is disabled
0
1
Receive input sampling occurs during the 9th time tick of a transmitted bit
(refer to Figure 11-19)
1
0
Receive input sampling occurs during the 13th time tick of a transmitted bit
(refer to Figure 11-19)
1
1
Reserved
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Serial Communication Interface (S12SCIV5)
11.3.2.6
SCI Control Register 2 (SCICR2)
Module Base + 0x0003
R
W
Reset
7
6
5
4
3
2
1
0
TIE
TCIE
RIE
ILIE
TE
RE
RWU
SBK
0
0
0
0
0
0
0
0
Figure 11-9. SCI Control Register 2 (SCICR2)
Read: Anytime
Write: Anytime
Table 11-10. SCICR2 Field Descriptions
Field
7
TIE
Description
Transmitter Interrupt Enable Bit — TIE enables the transmit data register empty flag, TDRE, to generate
interrupt requests.
0 TDRE interrupt requests disabled
1 TDRE interrupt requests enabled
6
TCIE
Transmission Complete Interrupt Enable Bit — TCIE enables the transmission complete flag, TC, to generate
interrupt requests.
0 TC interrupt requests disabled
1 TC interrupt requests enabled
5
RIE
Receiver Full Interrupt Enable Bit — RIE enables the receive data register full flag, RDRF, or the overrun flag,
OR, to generate interrupt requests.
0 RDRF and OR interrupt requests disabled
1 RDRF and OR interrupt requests enabled
4
ILIE
Idle Line Interrupt Enable Bit — ILIE enables the idle line flag, IDLE, to generate interrupt requests.
0 IDLE interrupt requests disabled
1 IDLE interrupt requests enabled
3
TE
Transmitter Enable Bit — TE enables the SCI transmitter and configures the TXD pin as being controlled by
the SCI. The TE bit can be used to queue an idle preamble.
0 Transmitter disabled
1 Transmitter enabled
2
RE
Receiver Enable Bit — RE enables the SCI receiver.
0 Receiver disabled
1 Receiver enabled
1
RWU
Receiver Wakeup Bit — Standby state
0 Normal operation.
1 RWU enables the wakeup function and inhibits further receiver interrupt requests. Normally, hardware wakes
the receiver by automatically clearing RWU.
0
SBK
Send Break Bit — Toggling SBK sends one break character (10 or 11 logic 0s, respectively 13 or 14 logics 0s
if BRK13 is set). Toggling implies clearing the SBK bit before the break character has finished transmitting. As
long as SBK is set, the transmitter continues to send complete break characters (10 or 11 bits, respectively 13
or 14 bits).
0 No break characters
1 Transmit break characters
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Serial Communication Interface (S12SCIV5)
11.3.2.7
SCI Status Register 1 (SCISR1)
The SCISR1 and SCISR2 registers provides inputs to the MCU for generation of SCI interrupts. Also,
these registers can be polled by the MCU to check the status of these bits. The flag-clearing procedures
require that the status register be read followed by a read or write to the SCI data register.It is permissible
to execute other instructions between the two steps as long as it does not compromise the handling of I/O,
but the order of operations is important for flag clearing.
Module Base + 0x0004
R
7
6
5
4
3
2
1
0
TDRE
TC
RDRF
IDLE
OR
NF
FE
PF
1
0
0
0
0
0
0
W
Reset
1
= Unimplemented or Reserved
Figure 11-10. SCI Status Register 1 (SCISR1)
Read: Anytime
Write: Has no meaning or effect
Table 11-11. SCISR1 Field Descriptions
Field
Description
7
TDRE
Transmit Data Register Empty Flag — TDRE is set when the transmit shift register receives a byte from the
SCI data register. When TDRE is 1, the transmit data register (SCIDRH/L) is empty and can receive a new value
to transmit.Clear TDRE by reading SCI status register 1 (SCISR1), with TDRE set and then writing to SCI data
register low (SCIDRL).
0 No byte transferred to transmit shift register
1 Byte transferred to transmit shift register; transmit data register empty
6
TC
Transmit Complete Flag — TC is set low when there is a transmission in progress or when a preamble or break
character is loaded. TC is set high when the TDRE flag is set and no data, preamble, or break character is being
transmitted.When TC is set, the TXD pin becomes idle (logic 1). Clear TC by reading SCI status register 1
(SCISR1) with TC set and then writing to SCI data register low (SCIDRL). TC is cleared automatically when data,
preamble, or break is queued and ready to be sent. TC is cleared in the event of a simultaneous set and clear of
the TC flag (transmission not complete).
0 Transmission in progress
1 No transmission in progress
5
RDRF
Receive Data Register Full Flag — RDRF is set when the data in the receive shift register transfers to the SCI
data register. Clear RDRF by reading SCI status register 1 (SCISR1) with RDRF set and then reading SCI data
register low (SCIDRL).
0 Data not available in SCI data register
1 Received data available in SCI data register
4
IDLE
Idle Line Flag — IDLE is set when 10 consecutive logic 1s (if M = 0) or 11 consecutive logic 1s (if M =1) appear
on the receiver input. Once the IDLE flag is cleared, a valid frame must again set the RDRF flag before an idle
condition can set the IDLE flag.Clear IDLE by reading SCI status register 1 (SCISR1) with IDLE set and then
reading SCI data register low (SCIDRL).
0 Receiver input is either active now or has never become active since the IDLE flag was last cleared
1 Receiver input has become idle
Note: When the receiver wakeup bit (RWU) is set, an idle line condition does not set the IDLE flag.
S12P-Family Reference Manual, Rev. 1.13
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Serial Communication Interface (S12SCIV5)
Table 11-11. SCISR1 Field Descriptions (continued)
Field
Description
3
OR
Overrun Flag — OR is set when software fails to read the SCI data register before the receive shift register
receives the next frame. The OR bit is set immediately after the stop bit has been completely received for the
second frame. The data in the shift register is lost, but the data already in the SCI data registers is not affected.
Clear OR by reading SCI status register 1 (SCISR1) with OR set and then reading SCI data register low
(SCIDRL).
0 No overrun
1 Overrun
Note: OR flag may read back as set when RDRF flag is clear. This may happen if the following sequence of
events occurs:
1. After the first frame is received, read status register SCISR1 (returns RDRF set and OR flag clear);
2. Receive second frame without reading the first frame in the data register (the second frame is not
received and OR flag is set);
3. Read data register SCIDRL (returns first frame and clears RDRF flag in the status register);
4. Read status register SCISR1 (returns RDRF clear and OR set).
Event 3 may be at exactly the same time as event 2 or any time after. When this happens, a dummy
SCIDRL read following event 4 will be required to clear the OR flag if further frames are to be received.
2
NF
Noise Flag — NF is set when the SCI detects noise on the receiver input. NF bit is set during the same cycle as
the RDRF flag but does not get set in the case of an overrun. Clear NF by reading SCI status register 1(SCISR1),
and then reading SCI data register low (SCIDRL).
0 No noise
1 Noise
1
FE
Framing Error Flag — FE is set when a logic 0 is accepted as the stop bit. FE bit is set during the same cycle
as the RDRF flag but does not get set in the case of an overrun. FE inhibits further data reception until it is
cleared. Clear FE by reading SCI status register 1 (SCISR1) with FE set and then reading the SCI data register
low (SCIDRL).
0 No framing error
1 Framing error
0
PF
Parity Error Flag — PF is set when the parity enable bit (PE) is set and the parity of the received data does not
match the parity type bit (PT). PF bit is set during the same cycle as the RDRF flag but does not get set in the
case of an overrun. Clear PF by reading SCI status register 1 (SCISR1), and then reading SCI data register low
(SCIDRL).
0 No parity error
1 Parity error
11.3.2.8
SCI Status Register 2 (SCISR2)
Module Base + 0x0005
7
R
W
Reset
AMAP
0
6
5
0
0
0
0
4
3
2
1
TXPOL
RXPOL
BRK13
TXDIR
0
0
0
0
0
RAF
0
= Unimplemented or Reserved
Figure 11-11. SCI Status Register 2 (SCISR2)
Read: Anytime
S12P-Family Reference Manual, Rev. 1.13
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Serial Communication Interface (S12SCIV5)
Write: Anytime
Table 11-12. SCISR2 Field Descriptions
Field
Description
7
AMAP
Alternative Map — This bit controls which registers sharing the same address space are accessible. In the reset
condition the SCI behaves as previous versions. Setting AMAP=1 allows the access to another set of control and
status registers and hides the baud rate and SCI control Register 1.
0 The registers labelled SCIBDH (0x0000),SCIBDL (0x0001), SCICR1 (0x0002) are accessible
1 The registers labelled SCIASR1 (0x0000),SCIACR1 (0x0001), SCIACR2 (0x00002) are accessible
4
TXPOL
Transmit Polarity — This bit control the polarity of the transmitted data. In NRZ format, a one is represented by
a mark and a zero is represented by a space for normal polarity, and the opposite for inverted polarity. In IrDA
format, a zero is represented by short high pulse in the middle of a bit time remaining idle low for a one for normal
polarity, and a zero is represented by short low pulse in the middle of a bit time remaining idle high for a one for
inverted polarity.
0 Normal polarity
1 Inverted polarity
3
RXPOL
Receive Polarity — This bit control the polarity of the received data. In NRZ format, a one is represented by a
mark and a zero is represented by a space for normal polarity, and the opposite for inverted polarity. In IrDA
format, a zero is represented by short high pulse in the middle of a bit time remaining idle low for a one for normal
polarity, and a zero is represented by short low pulse in the middle of a bit time remaining idle high for a one for
inverted polarity.
0 Normal polarity
1 Inverted polarity
2
BRK13
Break Transmit Character Length — This bit determines whether the transmit break character is 10 or 11 bit
respectively 13 or 14 bits long. The detection of a framing error is not affected by this bit.
0 Break character is 10 or 11 bit long
1 Break character is 13 or 14 bit long
1
TXDIR
Transmitter Pin Data Direction in Single-Wire Mode — This bit determines whether the TXD pin is going to
be used as an input or output, in the single-wire mode of operation. This bit is only relevant in the single-wire
mode of operation.
0 TXD pin to be used as an input in single-wire mode
1 TXD pin to be used as an output in single-wire mode
0
RAF
Receiver Active Flag — RAF is set when the receiver detects a logic 0 during the RT1 time period of the start
bit search. RAF is cleared when the receiver detects an idle character.
0 No reception in progress
1 Reception in progress
11.3.2.9
SCI Data Registers (SCIDRH, SCIDRL)
Module Base + 0x0006
7
R
6
R8
T8
W
Reset
0
0
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 11-12. SCI Data Registers (SCIDRH)
S12P-Family Reference Manual, Rev. 1.13
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Serial Communication Interface (S12SCIV5)
Module Base + 0x0007
7
6
5
4
3
2
1
0
R
R7
R6
R5
R4
R3
R2
R1
R0
W
T7
T6
T5
T4
T3
T2
T1
T0
0
0
0
0
0
0
0
0
Reset
Figure 11-13. SCI Data Registers (SCIDRL)
Read: Anytime; reading accesses SCI receive data register
Write: Anytime; writing accesses SCI transmit data register; writing to R8 has no effect
Table 11-13. SCIDRH and SCIDRL Field Descriptions
Field
Description
SCIDRH
7
R8
Received Bit 8 — R8 is the ninth data bit received when the SCI is configured for 9-bit data format (M = 1).
SCIDRH
6
T8
Transmit Bit 8 — T8 is the ninth data bit transmitted when the SCI is configured for 9-bit data format (M = 1).
SCIDRL
7:0
R[7:0]
T[7:0]
R7:R0 — Received bits seven through zero for 9-bit or 8-bit data formats
T7:T0 — Transmit bits seven through zero for 9-bit or 8-bit formats
NOTE
If the value of T8 is the same as in the previous transmission, T8 does not
have to be rewritten.The same value is transmitted until T8 is rewritten
In 8-bit data format, only SCI data register low (SCIDRL) needs to be
accessed.
When transmitting in 9-bit data format and using 8-bit write instructions,
write first to SCI data register high (SCIDRH), then SCIDRL.
11.4
Functional Description
This section provides a complete functional description of the SCI block, detailing the operation of the
design from the end user perspective in a number of subsections.
Figure 11-14 shows the structure of the SCI module. The SCI allows full duplex, asynchronous, serial
communication between the CPU and remote devices, including other CPUs. The SCI transmitter and
receiver operate independently, although they use the same baud rate generator. The CPU monitors the
status of the SCI, writes the data to be transmitted, and processes received data.
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Serial Communication Interface (S12SCIV5)
R8
IREN
SCI Data
Register
NF
FE
Ir_RXD
Bus
Clock
Receive
Shift Register
SCRXD
Receive
and Wakeup
Control
PF
RAF
RE
IDLE
RWU
RDRF
LOOPS
OR
RSRC
M
Baud Rate
Generator
IDLE
ILIE
RDRF/OR
Infrared
Receive
Decoder
R16XCLK
RXD
RIE
TIE
WAKE
Data Format
Control
ILT
PE
SBR12:SBR0
TDRE
TDRE
TC
SCI
Interrupt
Request
PT
TC
TCIE
TE
÷16
Transmit
Control
LOOPS
SBK
RSRC
T8
Transmit
Shift Register
RXEDGIE
Active Edge
Detect
RXEDGIF
BKDIF
RXD
SCI Data
Register
Break Detect
BKDFE
SCTXD
BKDIE
LIN Transmit BERRIF
Collision
Detect
BERRIE
R16XCLK
Infrared
Transmit
Encoder
BERRM[1:0]
Ir_TXD
TXD
R32XCLK
TNP[1:0]
IREN
Figure 11-14. Detailed SCI Block Diagram
11.4.1
Infrared Interface Submodule
This module provides the capability of transmitting narrow pulses to an IR LED and receiving narrow
pulses and transforming them to serial bits, which are sent to the SCI. The IrDA physical layer
specification defines a half-duplex infrared communication link for exchange data. The full standard
includes data rates up to 16 Mbits/s. This design covers only data rates between 2.4 Kbits/s and 115.2
Kbits/s.
The infrared submodule consists of two major blocks: the transmit encoder and the receive decoder. The
SCI transmits serial bits of data which are encoded by the infrared submodule to transmit a narrow pulse
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Serial Communication Interface (S12SCIV5)
for every zero bit. No pulse is transmitted for every one bit. When receiving data, the IR pulses should be
detected using an IR photo diode and transformed to CMOS levels by the IR receive decoder (external
from the MCU). The narrow pulses are then stretched by the infrared submodule to get back to a serial bit
stream to be received by the SCI.The polarity of transmitted pulses and expected receive pulses can be
inverted so that a direct connection can be made to external IrDA transceiver modules that uses active low
pulses.
The infrared submodule receives its clock sources from the SCI. One of these two clocks are selected in
the infrared submodule in order to generate either 3/16, 1/16, 1/32 or 1/4 narrow pulses during
transmission. The infrared block receives two clock sources from the SCI, R16XCLK and R32XCLK,
which are configured to generate the narrow pulse width during transmission. The R16XCLK and
R32XCLK are internal clocks with frequencies 16 and 32 times the baud rate respectively. Both
R16XCLK and R32XCLK clocks are used for transmitting data. The receive decoder uses only the
R16XCLK clock.
11.4.1.1
Infrared Transmit Encoder
The infrared transmit encoder converts serial bits of data from transmit shift register to the TXD pin. A
narrow pulse is transmitted for a zero bit and no pulse for a one bit. The narrow pulse is sent in the middle
of the bit with a duration of 1/32, 1/16, 3/16 or 1/4 of a bit time. A narrow high pulse is transmitted for a
zero bit when TXPOL is cleared, while a narrow low pulse is transmitted for a zero bit when TXPOL is set.
11.4.1.2
Infrared Receive Decoder
The infrared receive block converts data from the RXD pin to the receive shift register. A narrow pulse is
expected for each zero received and no pulse is expected for each one received. A narrow high pulse is
expected for a zero bit when RXPOL is cleared, while a narrow low pulse is expected for a zero bit when
RXPOL is set. This receive decoder meets the edge jitter requirement as defined by the IrDA serial infrared
physical layer specification.
11.4.2
LIN Support
This module provides some basic support for the LIN protocol. At first this is a break detect circuitry
making it easier for the LIN software to distinguish a break character from an incoming data stream. As a
further addition is supports a collision detection at the bit level as well as cancelling pending transmissions.
11.4.3
Data Format
The SCI uses the standard NRZ mark/space data format. When Infrared is enabled, the SCI uses RZI data
format where zeroes are represented by light pulses and ones remain low. See Figure 11-15 below.
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Serial Communication Interface (S12SCIV5)
8-Bit Data Format
(Bit M in SCICR1 Clear)
Start
Bit
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Possible
Parity
Bit
Bit 6
STOP
Bit
Bit 7
Next
Start
Bit
Standard
SCI Data
Infrared
SCI Data
9-Bit Data Format
(Bit M in SCICR1 Set)
Start
Bit
Bit 0
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
POSSIBLE
PARITY
Bit
Bit 6
Bit 7
Bit 8
STOP
Bit
NEXT
START
Bit
Standard
SCI Data
Infrared
SCI Data
Figure 11-15. SCI Data Formats
Each data character is contained in a frame that includes a start bit, eight or nine data bits, and a stop bit.
Clearing the M bit in SCI control register 1 configures the SCI for 8-bit data characters. A frame with eight
data bits has a total of 10 bits. Setting the M bit configures the SCI for nine-bit data characters. A frame
with nine data bits has a total of 11 bits.
Table 11-14. Example of 8-Bit Data Formats
Start
Bit
Data
Bits
Address
Bits
Parity
Bits
Stop
Bit
1
8
0
0
1
1
7
0
1
1
(1)
0
1
1
7
1
1. The address bit identifies the frame as an address
character. See Section 11.4.6.6, “Receiver Wakeup”.
When the SCI is configured for 9-bit data characters, the ninth data bit is the T8 bit in SCI data register
high (SCIDRH). It remains unchanged after transmission and can be used repeatedly without rewriting it.
A frame with nine data bits has a total of 11 bits.
Table 11-15. Example of 9-Bit Data Formats
Start
Bit
Data
Bits
Address
Bits
Parity
Bits
Stop
Bit
1
9
0
0
1
1
8
0
1
1
(1)
0
1
1
8
1
1. The address bit identifies the frame as an address
character. See Section 11.4.6.6, “Receiver Wakeup”.
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Serial Communication Interface (S12SCIV5)
11.4.4
Baud Rate Generation
A 13-bit modulus counter in the baud rate generator derives the baud rate for both the receiver and the
transmitter. The value from 0 to 8191 written to the SBR12:SBR0 bits determines the bus clock divisor.
The SBR bits are in the SCI baud rate registers (SCIBDH and SCIBDL). The baud rate clock is
synchronized with the bus clock and drives the receiver. The baud rate clock divided by 16 drives the
transmitter. The receiver has an acquisition rate of 16 samples per bit time.
Baud rate generation is subject to one source of error:
• Integer division of the bus clock may not give the exact target frequency.
Table 11-16 lists some examples of achieving target baud rates with a bus clock frequency of 25 MHz.
When IREN = 0 then,
SCI baud rate = SCI bus clock / (16 * SCIBR[12:0])
Table 11-16. Baud Rates (Example: Bus Clock = 25 MHz)
Bits
SBR[12:0]
Receiver
Clock (Hz)
Transmitter
Clock (Hz)
Target
Baud Rate
Error
(%)
41
609,756.1
38,109.8
38,400
.76
81
308,642.0
19,290.1
19,200
.47
163
153,374.2
9585.9
9,600
.16
326
76,687.1
4792.9
4,800
.15
651
38,402.5
2400.2
2,400
.01
1302
19,201.2
1200.1
1,200
.01
2604
9600.6
600.0
600
.00
5208
4800.0
300.0
300
.00
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Serial Communication Interface (S12SCIV5)
11.4.5
Transmitter
Internal Bus
Bus
Clock
÷ 16
Baud Divider
SCI Data Registers
11-Bit Transmit Register
H
8
7
6
5
4
3
2
1
0
TXPOL
SCTXD
L
MSB
M
Start
Stop
SBR12:SBR0
LOOP
CONTROL
TIE
TDRE IRQ
Break (All 0s)
Parity
Generation
Preamble (All 1s)
PT
Shift Enable
PE
Load from SCIDR
T8
To Receiver
LOOPS
RSRC
TDRE
Transmitter Control
TC
TC IRQ
TCIE
TE
BERRIF
BER IRQ
TCIE
SBK
BERRM[1:0]
Transmit
Collision Detect
SCTXD
SCRXD
(From Receiver)
Figure 11-16. Transmitter Block Diagram
11.4.5.1
Transmitter Character Length
The SCI transmitter can accommodate either 8-bit or 9-bit data characters. The state of the M bit in SCI
control register 1 (SCICR1) determines the length of data characters. When transmitting 9-bit data, bit T8
in SCI data register high (SCIDRH) is the ninth bit (bit 8).
11.4.5.2
Character Transmission
To transmit data, the MCU writes the data bits to the SCI data registers (SCIDRH/SCIDRL), which in turn
are transferred to the transmitter shift register. The transmit shift register then shifts a frame out through
the TXD pin, after it has prefaced them with a start bit and appended them with a stop bit. The SCI data
registers (SCIDRH and SCIDRL) are the write-only buffers between the internal data bus and the transmit
shift register.
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Serial Communication Interface (S12SCIV5)
The SCI also sets a flag, the transmit data register empty flag (TDRE), every time it transfers data from the
buffer (SCIDRH/L) to the transmitter shift register.The transmit driver routine may respond to this flag by
writing another byte to the Transmitter buffer (SCIDRH/SCIDRL), while the shift register is still shifting
out the first byte.
To initiate an SCI transmission:
1. Configure the SCI:
a) Select a baud rate. Write this value to the SCI baud registers (SCIBDH/L) to begin the baud
rate generator. Remember that the baud rate generator is disabled when the baud rate is zero.
Writing to the SCIBDH has no effect without also writing to SCIBDL.
b) Write to SCICR1 to configure word length, parity, and other configuration bits
(LOOPS,RSRC,M,WAKE,ILT,PE,PT).
c) Enable the transmitter, interrupts, receive, and wake up as required, by writing to the SCICR2
register bits (TIE,TCIE,RIE,ILIE,TE,RE,RWU,SBK). A preamble or idle character will now
be shifted out of the transmitter shift register.
2. Transmit Procedure for each byte:
a) Poll the TDRE flag by reading the SCISR1 or responding to the TDRE interrupt. Keep in mind
that the TDRE bit resets to one.
b) If the TDRE flag is set, write the data to be transmitted to SCIDRH/L, where the ninth bit is
written to the T8 bit in SCIDRH if the SCI is in 9-bit data format. A new transmission will not
result until the TDRE flag has been cleared.
3. Repeat step 2 for each subsequent transmission.
NOTE
The TDRE flag is set when the shift register is loaded with the next data to
be transmitted from SCIDRH/L, which happens, generally speaking, a little
over half-way through the stop bit of the previous frame. Specifically, this
transfer occurs 9/16ths of a bit time AFTER the start of the stop bit of the
previous frame.
Writing the TE bit from 0 to a 1 automatically loads the transmit shift register with a preamble of 10 logic
1s (if M = 0) or 11 logic 1s (if M = 1). After the preamble shifts out, control logic transfers the data from
the SCI data register into the transmit shift register. A logic 0 start bit automatically goes into the least
significant bit position of the transmit shift register. A logic 1 stop bit goes into the most significant bit
position.
Hardware supports odd or even parity. When parity is enabled, the most significant bit (MSB) of the data
character is the parity bit.
The transmit data register empty flag, TDRE, in SCI status register 1 (SCISR1) becomes set when the SCI
data register transfers a byte to the transmit shift register. The TDRE flag indicates that the SCI data
register can accept new data from the internal data bus. If the transmit interrupt enable bit, TIE, in SCI
control register 2 (SCICR2) is also set, the TDRE flag generates a transmitter interrupt request.
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Serial Communication Interface (S12SCIV5)
When the transmit shift register is not transmitting a frame, the TXD pin goes to the idle condition, logic
1. If at any time software clears the TE bit in SCI control register 2 (SCICR2), the transmitter enable signal
goes low and the transmit signal goes idle.
If software clears TE while a transmission is in progress (TC = 0), the frame in the transmit shift register
continues to shift out. To avoid accidentally cutting off the last frame in a message, always wait for TDRE
to go high after the last frame before clearing TE.
To separate messages with preambles with minimum idle line time, use this sequence between messages:
1. Write the last byte of the first message to SCIDRH/L.
2. Wait for the TDRE flag to go high, indicating the transfer of the last frame to the transmit shift
register.
3. Queue a preamble by clearing and then setting the TE bit.
4. Write the first byte of the second message to SCIDRH/L.
11.4.5.3
Break Characters
Writing a logic 1 to the send break bit, SBK, in SCI control register 2 (SCICR2) loads the transmit shift
register with a break character. A break character contains all logic 0s and has no start, stop, or parity bit.
Break character length depends on the M bit in SCI control register 1 (SCICR1). As long as SBK is at logic
1, transmitter logic continuously loads break characters into the transmit shift register. After software
clears the SBK bit, the shift register finishes transmitting the last break character and then transmits at least
one logic 1. The automatic logic 1 at the end of a break character guarantees the recognition of the start bit
of the next frame.
The SCI recognizes a break character when there are 10 or 11(M = 0 or M = 1) consecutive zero received.
Depending if the break detect feature is enabled or not receiving a break character has these effects on SCI
registers.
If the break detect feature is disabled (BKDFE = 0):
• Sets the framing error flag, FE
• Sets the receive data register full flag, RDRF
• Clears the SCI data registers (SCIDRH/L)
• May set the overrun flag, OR, noise flag, NF, parity error flag, PE, or the receiver active flag, RAF
(see 3.4.4 and 3.4.5 SCI Status Register 1 and 2)
If the break detect feature is enabled (BKDFE = 1) there are two scenarios1
The break is detected right from a start bit or is detected during a byte reception.
• Sets the break detect interrupt flag, BLDIF
• Does not change the data register full flag, RDRF or overrun flag OR
• Does not change the framing error flag FE, parity error flag PE.
• Does not clear the SCI data registers (SCIDRH/L)
• May set noise flag NF, or receiver active flag RAF.
1. A Break character in this context are either 10 or 11 consecutive zero received bits
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Serial Communication Interface (S12SCIV5)
Figure 11-17 shows two cases of break detect. In trace RXD_1 the break symbol starts with the start bit,
while in RXD_2 the break starts in the middle of a transmission. If BRKDFE = 1, in RXD_1 case there
will be no byte transferred to the receive buffer and the RDRF flag will not be modified. Also no framing
error or parity error will be flagged from this transfer. In RXD_2 case, however the break signal starts later
during the transmission. At the expected stop bit position the byte received so far will be transferred to the
receive buffer, the receive data register full flag will be set, a framing error and if enabled and appropriate
a parity error will be set. Once the break is detected the BRKDIF flag will be set.
Start Bit Position
Stop Bit Position
BRKDIF = 1
RXD_1
Zero Bit Counter
1
2
3
4
5
6
7
8
9
10 . . .
BRKDIF = 1
FE = 1
RXD_2
Zero Bit Counter
1
2
3
4
5
6
7
8
9
10
...
Figure 11-17. Break Detection if BRKDFE = 1 (M = 0)
11.4.5.4
Idle Characters
An idle character (or preamble) contains all logic 1s and has no start, stop, or parity bit. Idle character
length depends on the M bit in SCI control register 1 (SCICR1). The preamble is a synchronizing idle
character that begins the first transmission initiated after writing the TE bit from 0 to 1.
If the TE bit is cleared during a transmission, the TXD pin becomes idle after completion of the
transmission in progress. Clearing and then setting the TE bit during a transmission queues an idle
character to be sent after the frame currently being transmitted.
NOTE
When queueing an idle character, return the TE bit to logic 1 before the stop
bit of the current frame shifts out through the TXD pin. Setting TE after the
stop bit appears on TXD causes data previously written to the SCI data
register to be lost. Toggle the TE bit for a queued idle character while the
TDRE flag is set and immediately before writing the next byte to the SCI
data register.
If the TE bit is clear and the transmission is complete, the SCI is not the
master of the TXD pin
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Serial Communication Interface (S12SCIV5)
11.4.5.5
LIN Transmit Collision Detection
This module allows to check for collisions on the LIN bus.
LIN Physical Interface
Synchronizer Stage
Receive Shift
Register
Compare
RXD Pin
Bit Error
LIN Bus
Bus Clock
Sample
Point
Transmit Shift
Register
TXD Pin
Figure 11-18. Collision Detect Principle
If the bit error circuit is enabled (BERRM[1:0] = 0:1 or = 1:0]), the error detect circuit will compare the
transmitted and the received data stream at a point in time and flag any mismatch. The timing checks run
when transmitter is active (not idle). As soon as a mismatch between the transmitted data and the received
data is detected the following happens:
• The next bit transmitted will have a high level (TXPOL = 0) or low level (TXPOL = 1)
• The transmission is aborted and the byte in transmit buffer is discarded.
• the transmit data register empty and the transmission complete flag will be set
• The bit error interrupt flag, BERRIF, will be set.
• No further transmissions will take place until the BERRIF is cleared.
4
5
6
7
8
BERRM[1:0] = 0:1
9
10
11
12
13
14
15
0
Sampling End
3
Sampling Begin
Input Receive
Shift Register
2
Sampling End
Output Transmit
Shift Register
1
Sampling Begin
0
BERRM[1:0] = 1:1
Compare Sample Points
Figure 11-19. Timing Diagram Bit Error Detection
If the bit error detect feature is disabled, the bit error interrupt flag is cleared.
NOTE
The RXPOL and TXPOL bit should be set the same when transmission
collision detect feature is enabled, otherwise the bit error interrupt flag may
be set incorrectly.
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Serial Communication Interface (S12SCIV5)
11.4.6
Receiver
Internal Bus
SBR12:SBR0
RXPOL
Data
Recovery
Loop
Control
H
Start
11-Bit Receive Shift Register
8
7
6
5
4
3
2
1
0
L
All 1s
SCRXD
From TXD Pin
or Transmitter
Stop
Baud Divider
MSB
Bus
Clock
SCI Data Register
RE
RAF
LOOPS
RSRC
FE
M
WAKE
ILT
PE
PT
RWU
NF
Wakeup
Logic
PE
R8
Parity
Checking
Idle IRQ
IDLE
ILIE
BRKDFE
OR
Break
Detect Logic
RIE
BRKDIF
BRKDIE
Active Edge
Detect Logic
RDRF/OR
IRQ
RDRF
Break IRQ
RXEDGIF
RXEDGIE
RX Active Edge IRQ
Figure 11-20. SCI Receiver Block Diagram
11.4.6.1
Receiver Character Length
The SCI receiver can accommodate either 8-bit or 9-bit data characters. The state of the M bit in SCI
control register 1 (SCICR1) determines the length of data characters. When receiving 9-bit data, bit R8 in
SCI data register high (SCIDRH) is the ninth bit (bit 8).
11.4.6.2
Character Reception
During an SCI reception, the receive shift register shifts a frame in from the RXD pin. The SCI data register
is the read-only buffer between the internal data bus and the receive shift register.
After a complete frame shifts into the receive shift register, the data portion of the frame transfers to the
SCI data register. The receive data register full flag, RDRF, in SCI status register 1 (SCISR1) becomes set,
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Serial Communication Interface (S12SCIV5)
indicating that the received byte can be read. If the receive interrupt enable bit, RIE, in SCI control
register 2 (SCICR2) is also set, the RDRF flag generates an RDRF interrupt request.
11.4.6.3
Data Sampling
The RT clock rate. The RT clock is an internal signal with a frequency 16 times the baud rate. To adjust
for baud rate mismatch, the RT clock (see Figure 11-21) is re-synchronized:
• After every start bit
• After the receiver detects a data bit change from logic 1 to logic 0 (after the majority of data bit
samples at RT8, RT9, and RT10 returns a valid logic 1 and the majority of the next RT8, RT9, and
RT10 samples returns a valid logic 0)
To locate the start bit, data recovery logic does an asynchronous search for a logic 0 preceded by three logic
1s.When the falling edge of a possible start bit occurs, the RT clock begins to count to 16.
Start Bit
LSB
RXD
Samples
1
1
1
1
1
1
1
1
0
0
Start Bit
Qualification
0
0
Start Bit
Verification
0
0
0
Data
Sampling
RT4
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT10
RT9
RT8
RT7
RT6
RT5
RT4
RT3
RT2
RT1
RT1
RT1
RT1
RT1
RT1
RT1
RT1
RT CLock Count
RT1
RT Clock
Reset RT Clock
Figure 11-21. Receiver Data Sampling
To verify the start bit and to detect noise, data recovery logic takes samples at RT3, RT5, and RT7.
Figure 11-17 summarizes the results of the start bit verification samples.
Table 11-17. Start Bit Verification
RT3, RT5, and RT7 Samples
Start Bit Verification
Noise Flag
000
Yes
0
001
Yes
1
010
Yes
1
011
No
0
100
Yes
1
101
No
0
110
No
0
111
No
0
If start bit verification is not successful, the RT clock is reset and a new search for a start bit begins.
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Serial Communication Interface (S12SCIV5)
To determine the value of a data bit and to detect noise, recovery logic takes samples at RT8, RT9, and
RT10. Table 11-18 summarizes the results of the data bit samples.
Table 11-18. Data Bit Recovery
RT8, RT9, and RT10 Samples
Data Bit Determination
Noise Flag
000
0
0
001
0
1
010
0
1
011
1
1
100
0
1
101
1
1
110
1
1
111
1
0
NOTE
The RT8, RT9, and RT10 samples do not affect start bit verification. If any
or all of the RT8, RT9, and RT10 start bit samples are logic 1s following a
successful start bit verification, the noise flag (NF) is set and the receiver
assumes that the bit is a start bit (logic 0).
To verify a stop bit and to detect noise, recovery logic takes samples at RT8, RT9, and RT10. Table 11-19
summarizes the results of the stop bit samples.
Table 11-19. Stop Bit Recovery
RT8, RT9, and RT10 Samples
Framing Error Flag
Noise Flag
000
1
0
001
1
1
010
1
1
011
0
1
100
1
1
101
0
1
110
0
1
111
0
0
In Figure 11-22 the verification samples RT3 and RT5 determine that the first low detected was noise and
not the beginning of a start bit. The RT clock is reset and the start bit search begins again. The noise flag
is not set because the noise occurred before the start bit was found.
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Serial Communication Interface (S12SCIV5)
LSB
Start Bit
0
0
0
0
0
0
RT9
1
RT10
RT1
1
RT8
RT1
1
RT7
0
RT1
1
RT1
1
RT5
1
RT1
Samples
RT1
RXD
0
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT6
RT5
RT4
RT3
RT2
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 11-22. Start Bit Search Example 1
In Figure 11-23, verification sample at RT3 is high. The RT3 sample sets the noise flag. Although the
perceived bit time is misaligned, the data samples RT8, RT9, and RT10 are within the bit time and data
recovery is successful.
Perceived Start Bit
Actual Start Bit
LSB
1
0
RT1
RT1
RT1
RT1
RT1
1
0
0
0
0
0
RT10
1
RT9
1
RT8
1
RT7
1
RT1
RXD
Samples
RT7
RT6
RT5
RT4
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT6
RT5
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 11-23. Start Bit Search Example 2
In Figure 11-24, a large burst of noise is perceived as the beginning of a start bit, although the test sample
at RT5 is high. The RT5 sample sets the noise flag. Although this is a worst-case misalignment of perceived
bit time, the data samples RT8, RT9, and RT10 are within the bit time and data recovery is successful.
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Serial Communication Interface (S12SCIV5)
Perceived Start Bit
LSB
Actual Start Bit
RT1
RT1
0
1
0
0
0
0
RT10
0
RT9
1
RT8
1
RT7
1
RT1
Samples
RT1
RXD
RT9
RT8
RT7
RT6
RT5
RT4
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT6
RT5
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 11-24. Start Bit Search Example 3
Figure 11-25 shows the effect of noise early in the start bit time. Although this noise does not affect proper
synchronization with the start bit time, it does set the noise flag.
Perceived and Actual Start Bit
LSB
1
RT1
RT1
RT1
1
1
1
1
0
RT1
1
RT1
1
RT1
1
RT1
1
RT1
Samples
RT1
RXD
1
0
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT9
RT10
RT8
RT7
RT6
RT5
RT4
RT3
RT2
RT Clock Count
RT1
RT Clock
Reset RT Clock
Figure 11-25. Start Bit Search Example 4
Figure 11-26 shows a burst of noise near the beginning of the start bit that resets the RT clock. The sample
after the reset is low but is not preceded by three high samples that would qualify as a falling edge.
Depending on the timing of the start bit search and on the data, the frame may be missed entirely or it may
set the framing error flag.
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Start Bit
0
RT1
RT1
RT1
RT1
RT1
RT1
RT1
RT1
RT1
0
1
1
0
0
0
0
0
0
0
0
RT1
1
RT1
1
RT1
1
RT1
1
RT1
1
RT1
1
RT1
1
RT1
1
RT7
1
RT1
RXD
Samples
LSB
No Start Bit Found
RT1
RT1
RT1
RT1
RT6
RT5
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 11-26. Start Bit Search Example 5
In Figure 11-27, a noise burst makes the majority of data samples RT8, RT9, and RT10 high. This sets the
noise flag but does not reset the RT clock. In start bits only, the RT8, RT9, and RT10 data samples are
ignored.
Start Bit
LSB
RT1
RT1
1
0
0
0
0
1
0
1
RT10
RT1
1
RT9
RT1
1
RT8
1
RT7
1
RT1
1
RT1
1
RT1
1
RT1
1
RT1
Samples
RT1
RXD
RT3
RT2
RT1
RT16
RT15
RT14
RT13
RT12
RT11
RT6
RT5
RT4
RT3
RT Clock Count
RT2
RT Clock
Reset RT Clock
Figure 11-27. Start Bit Search Example 6
11.4.6.4
Framing Errors
If the data recovery logic does not detect a logic 1 where the stop bit should be in an incoming frame, it
sets the framing error flag, FE, in SCI status register 1 (SCISR1). A break character also sets the FE flag
because a break character has no stop bit. The FE flag is set at the same time that the RDRF flag is set.
11.4.6.5
Baud Rate Tolerance
A transmitting device may be operating at a baud rate below or above the receiver baud rate. Accumulated
bit time misalignment can cause one of the three stop bit data samples (RT8, RT9, and RT10) to fall outside
the actual stop bit. A noise error will occur if the RT8, RT9, and RT10 samples are not all the same logical
values. A framing error will occur if the receiver clock is misaligned in such a way that the majority of the
RT8, RT9, and RT10 stop bit samples are a logic zero.
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As the receiver samples an incoming frame, it re-synchronizes the RT clock on any valid falling edge
within the frame. Re synchronization within frames will correct a misalignment between transmitter bit
times and receiver bit times.
11.4.6.5.1
Slow Data Tolerance
Figure 11-28 shows how much a slow received frame can be misaligned without causing a noise error or
a framing error. The slow stop bit begins at RT8 instead of RT1 but arrives in time for the stop bit data
samples at RT8, RT9, and RT10.
MSB
Stop
RT16
RT15
RT14
RT13
RT12
RT11
RT10
RT9
RT8
RT7
RT6
RT5
RT4
RT3
RT2
RT1
Receiver
RT Clock
Data
Samples
Figure 11-28. Slow Data
Let’s take RTr as receiver RT clock and RTt as transmitter RT clock.
For an 8-bit data character, it takes the receiver 9 bit times x 16 RTr cycles +7 RTr cycles = 151 RTr cycles
to start data sampling of the stop bit.
With the misaligned character shown in Figure 11-28, the receiver counts 151 RTr cycles at the point when
the count of the transmitting device is 9 bit times x 16 RTt cycles = 144 RTt cycles.
The maximum percent difference between the receiver count and the transmitter count of a slow 8-bit data
character with no errors is:
((151 – 144) / 151) x 100 = 4.63%
For a 9-bit data character, it takes the receiver 10 bit times x 16 RTr cycles + 7 RTr cycles = 167 RTr cycles
to start data sampling of the stop bit.
With the misaligned character shown in Figure 11-28, the receiver counts 167 RTr cycles at the point when
the count of the transmitting device is 10 bit times x 16 RTt cycles = 160 RTt cycles.
The maximum percent difference between the receiver count and the transmitter count of a slow 9-bit
character with no errors is:
((167 – 160) / 167) X 100 = 4.19%
11.4.6.5.2
Fast Data Tolerance
Figure 11-29 shows how much a fast received frame can be misaligned. The fast stop bit ends at RT10
instead of RT16 but is still sampled at RT8, RT9, and RT10.
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Stop
Idle or Next Frame
RT16
RT15
RT14
RT13
RT12
RT11
RT10
RT9
RT8
RT7
RT6
RT5
RT4
RT3
RT2
RT1
Receiver
RT Clock
Data
Samples
Figure 11-29. Fast Data
For an 8-bit data character, it takes the receiver 9 bit times x 16 RTr cycles + 10 RTr cycles = 154 RTr cycles
to finish data sampling of the stop bit.
With the misaligned character shown in Figure 11-29, the receiver counts 154 RTr cycles at the point when
the count of the transmitting device is 10 bit times x 16 RTt cycles = 160 RTt cycles.
The maximum percent difference between the receiver count and the transmitter count of a fast 8-bit
character with no errors is:
((160 – 154) / 160) x 100 = 3.75%
For a 9-bit data character, it takes the receiver 10 bit times x 16 RTr cycles + 10 RTr cycles = 170 RTr cycles
to finish data sampling of the stop bit.
With the misaligned character shown in Figure 11-29, the receiver counts 170 RTr cycles at the point when
the count of the transmitting device is 11 bit times x 16 RTt cycles = 176 RTt cycles.
The maximum percent difference between the receiver count and the transmitter count of a fast 9-bit
character with no errors is:
((176 – 170) /176) x 100 = 3.40%
11.4.6.6
Receiver Wakeup
To enable the SCI to ignore transmissions intended only for other receivers in multiple-receiver systems,
the receiver can be put into a standby state. Setting the receiver wakeup bit, RWU, in SCI control register 2
(SCICR2) puts the receiver into standby state during which receiver interrupts are disabled.The SCI will
still load the receive data into the SCIDRH/L registers, but it will not set the RDRF flag.
The transmitting device can address messages to selected receivers by including addressing information in
the initial frame or frames of each message.
The WAKE bit in SCI control register 1 (SCICR1) determines how the SCI is brought out of the standby
state to process an incoming message. The WAKE bit enables either idle line wakeup or address mark
wakeup.
11.4.6.6.1
Idle Input line Wakeup (WAKE = 0)
In this wakeup method, an idle condition on the RXD pin clears the RWU bit and wakes up the SCI. The
initial frame or frames of every message contain addressing information. All receivers evaluate the
addressing information, and receivers for which the message is addressed process the frames that follow.
Any receiver for which a message is not addressed can set its RWU bit and return to the standby state. The
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RWU bit remains set and the receiver remains on standby until another idle character appears on the RXD
pin.
Idle line wakeup requires that messages be separated by at least one idle character and that no message
contains idle characters.
The idle character that wakes a receiver does not set the receiver idle bit, IDLE, or the receive data register
full flag, RDRF.
The idle line type bit, ILT, determines whether the receiver begins counting logic 1s as idle character bits
after the start bit or after the stop bit. ILT is in SCI control register 1 (SCICR1).
11.4.6.6.2
Address Mark Wakeup (WAKE = 1)
In this wakeup method, a logic 1 in the most significant bit (MSB) position of a frame clears the RWU bit
and wakes up the SCI. The logic 1 in the MSB position marks a frame as an address frame that contains
addressing information. All receivers evaluate the addressing information, and the receivers for which the
message is addressed process the frames that follow.Any receiver for which a message is not addressed can
set its RWU bit and return to the standby state. The RWU bit remains set and the receiver remains on
standby until another address frame appears on the RXD pin.
The logic 1 MSB of an address frame clears the receiver’s RWU bit before the stop bit is received and sets
the RDRF flag.
Address mark wakeup allows messages to contain idle characters but requires that the MSB be reserved
for use in address frames.
NOTE
With the WAKE bit clear, setting the RWU bit after the RXD pin has been
idle can cause the receiver to wake up immediately.
11.4.7
Single-Wire Operation
Normally, the SCI uses two pins for transmitting and receiving. In single-wire operation, the RXD pin is
disconnected from the SCI. The SCI uses the TXD pin for both receiving and transmitting.
Transmitter
Receiver
TXD
RXD
Figure 11-30. Single-Wire Operation (LOOPS = 1, RSRC = 1)
Enable single-wire operation by setting the LOOPS bit and the receiver source bit, RSRC, in SCI control
register 1 (SCICR1). Setting the LOOPS bit disables the path from the RXD pin to the receiver. Setting
the RSRC bit connects the TXD pin to the receiver. Both the transmitter and receiver must be enabled
(TE = 1 and RE = 1).The TXDIR bit (SCISR2[1]) determines whether the TXD pin is going to be used as
an input (TXDIR = 0) or an output (TXDIR = 1) in this mode of operation.
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NOTE
In single-wire operation data from the TXD pin is inverted if RXPOL is set.
11.4.8
Loop Operation
In loop operation the transmitter output goes to the receiver input. The RXD pin is disconnected from the
SCI.
Transmitter
TXD
Receiver
RXD
Figure 11-31. Loop Operation (LOOPS = 1, RSRC = 0)
Enable loop operation by setting the LOOPS bit and clearing the RSRC bit in SCI control register 1
(SCICR1). Setting the LOOPS bit disables the path from the RXD pin to the receiver. Clearing the RSRC
bit connects the transmitter output to the receiver input. Both the transmitter and receiver must be enabled
(TE = 1 and RE = 1).
NOTE
In loop operation data from the transmitter is not recognized by the receiver
if RXPOL and TXPOL are not the same.
11.5
Initialization/Application Information
11.5.1
Reset Initialization
See Section 11.3.2, “Register Descriptions”.
11.5.2
11.5.2.1
Modes of Operation
Run Mode
Normal mode of operation.
To initialize a SCI transmission, see Section 11.4.5.2, “Character Transmission”.
11.5.2.2
Wait Mode
SCI operation in wait mode depends on the state of the SCISWAI bit in the SCI control register 1
(SCICR1).
• If SCISWAI is clear, the SCI operates normally when the CPU is in wait mode.
• If SCISWAI is set, SCI clock generation ceases and the SCI module enters a power-conservation
state when the CPU is in wait mode. Setting SCISWAI does not affect the state of the receiver
enable bit, RE, or the transmitter enable bit, TE.
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If SCISWAI is set, any transmission or reception in progress stops at wait mode entry. The
transmission or reception resumes when either an internal or external interrupt brings the CPU out
of wait mode. Exiting wait mode by reset aborts any transmission or reception in progress and
resets the SCI.
11.5.2.3
Stop Mode
The SCI is inactive during stop mode for reduced power consumption. The STOP instruction does not
affect the SCI register states, but the SCI bus clock will be disabled. The SCI operation resumes from
where it left off after an external interrupt brings the CPU out of stop mode. Exiting stop mode by reset
aborts any transmission or reception in progress and resets the SCI.
The receive input active edge detect circuit is still active in stop mode. An active edge on the receive input
can be used to bring the CPU out of stop mode.
11.5.3
Interrupt Operation
This section describes the interrupt originated by the SCI block.The MCU must service the interrupt
requests. Table 11-20 lists the eight interrupt sources of the SCI.
Table 11-20. SCI Interrupt Sources
Interrupt
Source
Local Enable
TDRE
SCISR1[7]
TIE
TC
SCISR1[6]
TCIE
RDRF
SCISR1[5]
RIE
OR
SCISR1[3]
IDLE
SCISR1[4]
RXEDGIF SCIASR1[7]
Description
Active high level. Indicates that a byte was transferred from SCIDRH/L to the
transmit shift register.
Active high level. Indicates that a transmit is complete.
Active high level. The RDRF interrupt indicates that received data is available
in the SCI data register.
Active high level. This interrupt indicates that an overrun condition has occurred.
ILIE
Active high level. Indicates that receiver input has become idle.
RXEDGIE
Active high level. Indicates that an active edge (falling for RXPOL = 0, rising for
RXPOL = 1) was detected.
BERRIF
SCIASR1[1]
BERRIE
Active high level. Indicates that a mismatch between transmitted and received data
in a single wire application has happened.
BKDIF
SCIASR1[0]
BRKDIE
Active high level. Indicates that a break character has been received.
11.5.3.1
Description of Interrupt Operation
The SCI only originates interrupt requests. The following is a description of how the SCI makes a request
and how the MCU should acknowledge that request. The interrupt vector offset and interrupt number are
chip dependent. The SCI only has a single interrupt line (SCI Interrupt Signal, active high operation) and
all the following interrupts, when generated, are ORed together and issued through that port.
11.5.3.1.1
TDRE Description
The TDRE interrupt is set high by the SCI when the transmit shift register receives a byte from the SCI
data register. A TDRE interrupt indicates that the transmit data register (SCIDRH/L) is empty and that a
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new byte can be written to the SCIDRH/L for transmission.Clear TDRE by reading SCI status register 1
with TDRE set and then writing to SCI data register low (SCIDRL).
11.5.3.1.2
TC Description
The TC interrupt is set by the SCI when a transmission has been completed. Transmission is completed
when all bits including the stop bit (if transmitted) have been shifted out and no data is queued to be
transmitted. No stop bit is transmitted when sending a break character and the TC flag is set (providing
there is no more data queued for transmission) when the break character has been shifted out. A TC
interrupt indicates that there is no transmission in progress. TC is set high when the TDRE flag is set and
no data, preamble, or break character is being transmitted. When TC is set, the TXD pin becomes idle
(logic 1). Clear TC by reading SCI status register 1 (SCISR1) with TC set and then writing to SCI data
register low (SCIDRL).TC is cleared automatically when data, preamble, or break is queued and ready to
be sent.
11.5.3.1.3
RDRF Description
The RDRF interrupt is set when the data in the receive shift register transfers to the SCI data register. A
RDRF interrupt indicates that the received data has been transferred to the SCI data register and that the
byte can now be read by the MCU. The RDRF interrupt is cleared by reading the SCI status register one
(SCISR1) and then reading SCI data register low (SCIDRL).
11.5.3.1.4
OR Description
The OR interrupt is set when software fails to read the SCI data register before the receive shift register
receives the next frame. The newly acquired data in the shift register will be lost in this case, but the data
already in the SCI data registers is not affected. The OR interrupt is cleared by reading the SCI status
register one (SCISR1) and then reading SCI data register low (SCIDRL).
11.5.3.1.5
IDLE Description
The IDLE interrupt is set when 10 consecutive logic 1s (if M = 0) or 11 consecutive logic 1s (if M = 1)
appear on the receiver input. Once the IDLE is cleared, a valid frame must again set the RDRF flag before
an idle condition can set the IDLE flag. Clear IDLE by reading SCI status register 1 (SCISR1) with IDLE
set and then reading SCI data register low (SCIDRL).
11.5.3.1.6
RXEDGIF Description
The RXEDGIF interrupt is set when an active edge (falling if RXPOL = 0, rising if RXPOL = 1) on the
RXD pin is detected. Clear RXEDGIF by writing a “1” to the SCIASR1 SCI alternative status register 1.
11.5.3.1.7
BERRIF Description
The BERRIF interrupt is set when a mismatch between the transmitted and the received data in a single
wire application like LIN was detected. Clear BERRIF by writing a “1” to the SCIASR1 SCI alternative
status register 1. This flag is also cleared if the bit error detect feature is disabled.
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11.5.3.1.8
BKDIF Description
The BKDIF interrupt is set when a break signal was received. Clear BKDIF by writing a “1” to the
SCIASR1 SCI alternative status register 1. This flag is also cleared if break detect feature is disabled.
11.5.4
Recovery from Wait Mode
The SCI interrupt request can be used to bring the CPU out of wait mode.
11.5.5
Recovery from Stop Mode
An active edge on the receive input can be used to bring the CPU out of stop mode.
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Chapter 12
Serial Peripheral Interface (S12SPIV5)
Table 12-1. Revision History
Revision
Number
Revision Date
Sections
Affected
V05.00
24 Mar 2005
12.3.2/12-403
12.1
Description of Changes
- Added 16-bit transfer width feature.
Introduction
The SPI module allows a duplex, synchronous, serial communication between the MCU and peripheral
devices. Software can poll the SPI status flags or the SPI operation can be interrupt driven.
12.1.1
Glossary of Terms
SPI
SS
SCK
MOSI
MISO
MOMI
SISO
12.1.2
Serial Peripheral Interface
Slave Select
Serial Clock
Master Output, Slave Input
Master Input, Slave Output
Master Output, Master Input
Slave Input, Slave Output
Features
The SPI includes these distinctive features:
• Master mode and slave mode
• Selectable 8 or 16-bit transfer width
• Bidirectional mode
• Slave select output
• Mode fault error flag with CPU interrupt capability
• Double-buffered data register
• Serial clock with programmable polarity and phase
• Control of SPI operation during wait mode
12.1.3
Modes of Operation
The SPI functions in three modes: run, wait, and stop.
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•
•
•
Run mode
This is the basic mode of operation.
Wait mode
SPI operation in wait mode is a configurable low power mode, controlled by the SPISWAI bit
located in the SPICR2 register. In wait mode, if the SPISWAI bit is clear, the SPI operates like in
run mode. If the SPISWAI bit is set, the SPI goes into a power conservative state, with the SPI clock
generation turned off. If the SPI is configured as a master, any transmission in progress stops, but
is resumed after CPU goes into run mode. If the SPI is configured as a slave, reception and
transmission of data continues, so that the slave stays synchronized to the master.
Stop mode
The SPI is inactive in stop mode for reduced power consumption. If the SPI is configured as a
master, any transmission in progress stops, but is resumed after CPU goes into run mode. If the SPI
is configured as a slave, reception and transmission of data continues, so that the slave stays
synchronized to the master.
For a detailed description of operating modes, please refer to Section 12.4.7, “Low Power Mode Options”.
12.1.4
Block Diagram
Figure 12-1 gives an overview on the SPI architecture. The main parts of the SPI are status, control and
data registers, shifter logic, baud rate generator, master/slave control logic, and port control logic.
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SPI
2
SPI Control Register 1
BIDIROE
2
SPI Control Register 2
SPC0
SPI Status Register
SPIF MODF SPTEF
Slave
Control
CPOL
CPHA
Phase + SCK In
Slave Baud Rate Polarity
Control
Master Baud Rate
Phase + SCK Out
Polarity
Control
Interrupt Control
SPI
Interrupt
Request
Baud Rate Generator
Master
Control
Counter
Bus Clock
Prescaler Clock Select
SPPR
3
SPR
MOSI
Port
Control
Logic
SCK
SS
Baud Rate
Shift
Clock
Sample
Clock
3
Shifter
SPI Baud Rate Register
Data In
LSBFE=1
LSBFE=0
LSBFE=1
MSB
SPI Data Register
LSBFE=0
LSBFE=0 LSB
LSBFE=1
Data Out
Figure 12-1. SPI Block Diagram
12.2
External Signal Description
This section lists the name and description of all ports including inputs and outputs that do, or may, connect
off chip. The SPI module has a total of four external pins.
12.2.1
MOSI — Master Out/Slave In Pin
This pin is used to transmit data out of the SPI module when it is configured as a master and receive data
when it is configured as slave.
12.2.2
MISO — Master In/Slave Out Pin
This pin is used to transmit data out of the SPI module when it is configured as a slave and receive data
when it is configured as master.
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12.2.3
SS — Slave Select Pin
This pin is used to output the select signal from the SPI module to another peripheral with which a data
transfer is to take place when it is configured as a master and it is used as an input to receive the slave select
signal when the SPI is configured as slave.
12.2.4
SCK — Serial Clock Pin
In master mode, this is the synchronous output clock. In slave mode, this is the synchronous input clock.
12.3
Memory Map and Register Definition
This section provides a detailed description of address space and registers used by the SPI.
12.3.1
Module Memory Map
The memory map for the SPI is given in Figure 12-2. The address listed for each register is the sum of a
base address and an address offset. The base address is defined at the SoC level and the address offset is
defined at the module level. Reads from the reserved bits return zeros and writes to the reserved bits have
no effect.
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
SPIE
SPE
SPTIE
MSTR
CPOL
CPHA
SSOE
LSBFE
MODFEN
BIDIROE
SPISWAI
SPC0
SPR2
SPR1
SPR0
0x0000
SPICR1
R
W
0x0001
SPICR2
R
W
0
0x0002
SPIBR
R
W
0
0x0003
SPISR
R
W
0x0004
SPIDRH
XFRW
0
0
0
SPPR2
SPPR1
SPPR0
SPIF
0
SPTEF
MODF
0
0
0
0
R
W
R15
T15
R14
T14
R13
T13
R12
T12
R11
T11
R10
T10
R9
T9
R8
T8
0x0005
SPIDRL
R
W
R7
T7
R6
T6
R5
T5
R4
T4
R3
T3
R2
T2
R1
T1
R0
T0
0x0006
Reserved
R
W
0x0007
Reserved
R
W
= Unimplemented or Reserved
Figure 12-2. SPI Register Summary
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12.3.2
Register Descriptions
This section consists of register descriptions in address order. Each description includes a standard register
diagram with an associated figure number. Details of register bit and field function follow the register
diagrams, in bit order.
12.3.2.1
SPI Control Register 1 (SPICR1)
Module Base +0x0000
R
W
Reset
7
6
5
4
3
2
1
0
SPIE
SPE
SPTIE
MSTR
CPOL
CPHA
SSOE
LSBFE
0
0
0
0
0
1
0
0
Figure 12-3. SPI Control Register 1 (SPICR1)
Read: Anytime
Write: Anytime
Table 12-2. SPICR1 Field Descriptions
Field
Description
7
SPIE
SPI Interrupt Enable Bit — This bit enables SPI interrupt requests, if SPIF or MODF status flag is set.
0 SPI interrupts disabled.
1 SPI interrupts enabled.
6
SPE
SPI System Enable Bit — This bit enables the SPI system and dedicates the SPI port pins to SPI system
functions. If SPE is cleared, SPI is disabled and forced into idle state, status bits in SPISR register are reset.
0 SPI disabled (lower power consumption).
1 SPI enabled, port pins are dedicated to SPI functions.
5
SPTIE
SPI Transmit Interrupt Enable — This bit enables SPI interrupt requests, if SPTEF flag is set.
0 SPTEF interrupt disabled.
1 SPTEF interrupt enabled.
4
MSTR
SPI Master/Slave Mode Select Bit — This bit selects whether the SPI operates in master or slave mode.
Switching the SPI from master to slave or vice versa forces the SPI system into idle state.
0 SPI is in slave mode.
1 SPI is in master mode.
3
CPOL
SPI Clock Polarity Bit — This bit selects an inverted or non-inverted SPI clock. To transmit data between SPI
modules, the SPI modules must have identical CPOL values. In master mode, a change of this bit will abort a
transmission in progress and force the SPI system into idle state.
0 Active-high clocks selected. In idle state SCK is low.
1 Active-low clocks selected. In idle state SCK is high.
2
CPHA
SPI Clock Phase Bit — This bit is used to select the SPI clock format. In master mode, a change of this bit will
abort a transmission in progress and force the SPI system into idle state.
0 Sampling of data occurs at odd edges (1,3,5,...) of the SCK clock.
1 Sampling of data occurs at even edges (2,4,6,...) of the SCK clock.
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Table 12-2. SPICR1 Field Descriptions (continued)
Field
Description
1
SSOE
Slave Select Output Enable — The SS output feature is enabled only in master mode, if MODFEN is set, by
asserting the SSOE as shown in Table 12-3. In master mode, a change of this bit will abort a transmission in
progress and force the SPI system into idle state.
0
LSBFE
LSB-First Enable — This bit does not affect the position of the MSB and LSB in the data register. Reads and
writes of the data register always have the MSB in the highest bit position. In master mode, a change of this bit
will abort a transmission in progress and force the SPI system into idle state.
0 Data is transferred most significant bit first.
1 Data is transferred least significant bit first.
Table 12-3. SS Input / Output Selection
MODFEN
12.3.2.2
SSOE
Master Mode
Slave Mode
0
0
SS not used by SPI
SS input
0
1
SS not used by SPI
SS input
1
0
SS input with MODF feature
SS input
1
1
SS is slave select output
SS input
SPI Control Register 2 (SPICR2)
Module Base +0x0001
7
R
0
W
Reset
0
6
XFRW
0
5
0
0
4
3
MODFEN
BIDIROE
0
0
2
0
0
1
0
SPISWAI
SPC0
0
0
= Unimplemented or Reserved
Figure 12-4. SPI Control Register 2 (SPICR2)
Read: Anytime
Write: Anytime; writes to the reserved bits have no effect
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Serial Peripheral Interface (S12SPIV5)
Table 12-4. SPICR2 Field Descriptions
Field
Description
6
XFRW
Transfer Width — This bit is used for selecting the data transfer width. If 8-bit transfer width is selected, SPIDRL
becomes the dedicated data register and SPIDRH is unused. If 16-bit transfer width is selected, SPIDRH and
SPIDRL form a 16-bit data register. Please refer to Section 12.3.2.4, “SPI Status Register (SPISR) for
information about transmit/receive data handling and the interrupt flag clearing mechanism. In master mode, a
change of this bit will abort a transmission in progress and force the SPI system into idle state.
0 8-bit Transfer Width (n = 8)(1)
1 16-bit Transfer Width (n = 16)1
4
MODFEN
Mode Fault Enable Bit — This bit allows the MODF failure to be detected. If the SPI is in master mode and
MODFEN is cleared, then the SS port pin is not used by the SPI. In slave mode, the SS is available only as an
input regardless of the value of MODFEN. For an overview on the impact of the MODFEN bit on the SS port pin
configuration, refer to Table 12-3. In master mode, a change of this bit will abort a transmission in progress and
force the SPI system into idle state.
0 SS port pin is not used by the SPI.
1 SS port pin with MODF feature.
3
BIDIROE
Output Enable in the Bidirectional Mode of Operation — This bit controls the MOSI and MISO output buffer
of the SPI, when in bidirectional mode of operation (SPC0 is set). In master mode, this bit controls the output
buffer of the MOSI port, in slave mode it controls the output buffer of the MISO port. In master mode, with SPC0
set, a change of this bit will abort a transmission in progress and force the SPI into idle state.
0 Output buffer disabled.
1 Output buffer enabled.
1
SPISWAI
SPI Stop in Wait Mode Bit — This bit is used for power conservation while in wait mode.
0 SPI clock operates normally in wait mode.
1 Stop SPI clock generation when in wait mode.
0
Serial Pin Control Bit 0 — This bit enables bidirectional pin configurations as shown in Table 12-5. In master
SPC0
mode, a change of this bit will abort a transmission in progress and force the SPI system into idle state.
1. n is used later in this document as a placeholder for the selected transfer width.
Table 12-5. Bidirectional Pin Configurations
Pin Mode
SPC0
BIDIROE
MISO
MOSI
Master Mode of Operation
Normal
0
Bidirectional
1
X
Master In
0
MISO not used by SPI
1
Master Out
Master In
Master I/O
Slave Mode of Operation
Normal
0
Bidirectional
1
X
Slave Out
Slave In
0
Slave In
MOSI not used by SPI
1
Slave I/O
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Serial Peripheral Interface (S12SPIV5)
12.3.2.3
SPI Baud Rate Register (SPIBR)
Module Base +0x0002
7
R
6
0
W
Reset
0
5
4
3
SPPR2
SPPR1
SPPR0
0
0
0
0
0
2
1
0
SPR2
SPR1
SPR0
0
0
0
= Unimplemented or Reserved
Figure 12-5. SPI Baud Rate Register (SPIBR)
Read: Anytime
Write: Anytime; writes to the reserved bits have no effect
Table 12-6. SPIBR Field Descriptions
Field
Description
6–4
SPPR[2:0]
SPI Baud Rate Preselection Bits — These bits specify the SPI baud rates as shown in Table 12-7. In master
mode, a change of these bits will abort a transmission in progress and force the SPI system into idle state.
2–0
SPR[2:0]
SPI Baud Rate Selection Bits — These bits specify the SPI baud rates as shown in Table 12-7. In master mode,
a change of these bits will abort a transmission in progress and force the SPI system into idle state.
The baud rate divisor equation is as follows:
BaudRateDivisor = (SPPR + 1) • 2(SPR + 1)
Eqn. 12-1
The baud rate can be calculated with the following equation:
Baud Rate = BusClock / BaudRateDivisor
Eqn. 12-2
NOTE
For maximum allowed baud rates, please refer to the SPI Electrical
Specification in the Electricals chapter of this data sheet.
Table 12-7. Example SPI Baud Rate Selection (25 MHz Bus Clock) (Sheet 1 of 3)
SPPR2
SPPR1
SPPR0
SPR2
SPR1
SPR0
Baud Rate
Divisor
Baud Rate
0
0
0
0
0
0
2
12.5 Mbit/s
0
0
0
0
0
1
4
6.25 Mbit/s
0
0
0
0
1
0
8
3.125 Mbit/s
0
0
0
0
1
1
16
1.5625 Mbit/s
0
0
0
1
0
0
32
781.25 kbit/s
0
0
0
1
0
1
64
390.63 kbit/s
0
0
0
1
1
0
128
195.31 kbit/s
0
0
0
1
1
1
256
97.66 kbit/s
0
0
1
0
0
0
4
6.25 Mbit/s
0
0
1
0
0
1
8
3.125 Mbit/s
0
0
1
0
1
0
16
1.5625 Mbit/s
0
0
1
0
1
1
32
781.25 kbit/s
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Serial Peripheral Interface (S12SPIV5)
Table 12-7. Example SPI Baud Rate Selection (25 MHz Bus Clock) (Sheet 2 of 3)
Baud Rate
Divisor
Baud Rate
0
64
390.63 kbit/s
1
128
195.31 kbit/s
1
0
256
97.66 kbit/s
1
1
512
48.83 kbit/s
0
0
0
6
4.16667 Mbit/s
0
0
1
12
2.08333 Mbit/s
0
0
1
0
24
1.04167 Mbit/s
0
0
1
1
48
520.83 kbit/s
1
0
1
0
0
96
260.42 kbit/s
1
0
1
0
1
192
130.21 kbit/s
0
1
0
1
1
0
384
65.10 kbit/s
0
1
0
1
1
1
768
32.55 kbit/s
0
1
1
0
0
0
8
3.125 Mbit/s
0
1
1
0
0
1
16
1.5625 Mbit/s
0
1
1
0
1
0
32
781.25 kbit/s
0
1
1
0
1
1
64
390.63 kbit/s
0
1
1
1
0
0
128
195.31 kbit/s
0
1
1
1
0
1
256
97.66 kbit/s
0
1
1
1
1
0
512
48.83 kbit/s
0
1
1
1
1
1
1024
24.41 kbit/s
1
0
0
0
0
0
10
2.5 Mbit/s
1
0
0
0
0
1
20
1.25 Mbit/s
1
0
0
0
1
0
40
625 kbit/s
1
0
0
0
1
1
80
312.5 kbit/s
1
0
0
1
0
0
160
156.25 kbit/s
1
0
0
1
0
1
320
78.13 kbit/s
1
0
0
1
1
0
640
39.06 kbit/s
1
0
0
1
1
1
1280
19.53 kbit/s
1
0
1
0
0
0
12
2.08333 Mbit/s
1
0
1
0
0
1
24
1.04167 Mbit/s
1
0
1
0
1
0
48
520.83 kbit/s
1
0
1
0
1
1
96
260.42 kbit/s
1
0
1
1
0
0
192
130.21 kbit/s
1
0
1
1
0
1
384
65.10 kbit/s
1
0
1
1
1
0
768
32.55 kbit/s
1
0
1
1
1
1
1536
16.28 kbit/s
1
1
0
0
0
0
14
1.78571 Mbit/s
1
1
0
0
0
1
28
892.86 kbit/s
1
1
0
0
1
0
56
446.43 kbit/s
1
1
0
0
1
1
112
223.21 kbit/s
1
1
0
1
0
0
224
111.61 kbit/s
1
1
0
1
0
1
448
55.80 kbit/s
SPPR2
SPPR1
SPPR0
SPR2
SPR1
SPR0
0
0
1
1
0
0
0
1
1
0
0
0
1
1
0
0
1
1
0
1
0
0
1
0
0
1
0
1
0
0
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Serial Peripheral Interface (S12SPIV5)
Table 12-7. Example SPI Baud Rate Selection (25 MHz Bus Clock) (Sheet 3 of 3)
Baud Rate
Divisor
Baud Rate
0
896
27.90 kbit/s
1
1792
13.95 kbit/s
0
0
16
1.5625 Mbit/s
0
1
32
781.25 kbit/s
0
1
0
64
390.63 kbit/s
0
1
1
128
195.31 kbit/s
1
1
0
0
256
97.66 kbit/s
1
1
0
1
512
48.83 kbit/s
1
1
1
1
0
1024
24.41 kbit/s
1
1
1
1
1
2048
12.21 kbit/s
SPPR2
SPPR1
SPPR0
SPR2
SPR1
SPR0
1
1
0
1
1
1
1
0
1
1
1
1
1
0
1
1
1
0
1
1
1
1
1
1
1
1
1
1
1
1
12.3.2.4
SPI Status Register (SPISR)
Module Base +0x0003
R
7
6
5
4
3
2
1
0
SPIF
0
SPTEF
MODF
0
0
0
0
0
0
1
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 12-6. SPI Status Register (SPISR)
Read: Anytime
Write: Has no effect
Table 12-8. SPISR Field Descriptions
Field
Description
7
SPIF
SPIF Interrupt Flag — This bit is set after received data has been transferred into the SPI data register. For
information about clearing SPIF Flag, please refer to Table 12-9.
0 Transfer not yet complete.
1 New data copied to SPIDR.
5
SPTEF
SPI Transmit Empty Interrupt Flag — If set, this bit indicates that the transmit data register is empty. For
information about clearing this bit and placing data into the transmit data register, please refer to Table 12-10.
0 SPI data register not empty.
1 SPI data register empty.
4
MODF
Mode Fault Flag — This bit is set if the SS input becomes low while the SPI is configured as a master and mode
fault detection is enabled, MODFEN bit of SPICR2 register is set. Refer to MODFEN bit description in
Section 12.3.2.2, “SPI Control Register 2 (SPICR2)”. The flag is cleared automatically by a read of the SPI status
register (with MODF set) followed by a write to the SPI control register 1.
0 Mode fault has not occurred.
1 Mode fault has occurred.
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Serial Peripheral Interface (S12SPIV5)
Table 12-9. SPIF Interrupt Flag Clearing Sequence
XFRW Bit
SPIF Interrupt Flag Clearing Sequence
0
Read SPISR with SPIF == 1
1
Read SPISR with SPIF == 1
then
Read SPIDRL
Byte Read SPIDRL (1)
or
then Byte Read SPIDRH (2)
Byte Read SPIDRL
or
Word Read (SPIDRH:SPIDRL)
1. Data in SPIDRH is lost in this case.
2. SPIDRH can be read repeatedly without any effect on SPIF. SPIF Flag is cleared only by the read
of SPIDRL after reading SPISR with SPIF == 1.
Table 12-10. SPTEF Interrupt Flag Clearing Sequence
XFRW Bit
SPTEF Interrupt Flag Clearing Sequence
0
Read SPISR with SPTEF == 1 then
1
Read SPISR with SPTEF == 1
Write to SPIDRL (1)
Byte Write to SPIDRL 1(2)
or
then Byte Write to SPIDRH 1(3) Byte Write to SPIDRL 1
or
Word Write to (SPIDRH:SPIDRL) 1
1. Any write to SPIDRH or SPIDRL with SPTEF == 0 is effectively ignored.
2. Data in SPIDRH is undefined in this case.
3. SPIDRH can be written repeatedly without any effect on SPTEF. SPTEF Flag is cleared only by
writing to SPIDRL after reading SPISR with SPTEF == 1.
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Serial Peripheral Interface (S12SPIV5)
12.3.2.5
SPI Data Register (SPIDR = SPIDRH:SPIDRL)
Module Base +0x0004
7
6
5
4
3
2
1
0
R
R15
R14
R13
R12
R11
R10
R9
R8
W
T15
T14
T13
T12
T11
T10
T9
T8
0
0
0
0
0
0
0
0
Reset
Figure 12-7. SPI Data Register High (SPIDRH)
Module Base +0x0005
7
6
5
4
3
2
1
0
R
R7
R6
R5
R4
R3
R2
R1
R0
W
T7
T6
T5
T4
T3
T2
T1
T0
0
0
0
0
0
0
0
0
Reset
Figure 12-8. SPI Data Register Low (SPIDRL)
Read: Anytime; read data only valid when SPIF is set
Write: Anytime
The SPI data register is both the input and output register for SPI data. A write to this register
allows data to be queued and transmitted. For an SPI configured as a master, queued data is
transmitted immediately after the previous transmission has completed. The SPI transmitter empty
flag SPTEF in the SPISR register indicates when the SPI data register is ready to accept new data.
Received data in the SPIDR is valid when SPIF is set.
If SPIF is cleared and data has been received, the received data is transferred from the receive shift
register to the SPIDR and SPIF is set.
If SPIF is set and not serviced, and a second data value has been received, the second received data
is kept as valid data in the receive shift register until the start of another transmission. The data in
the SPIDR does not change.
If SPIF is set and valid data is in the receive shift register, and SPIF is serviced before the start of
a third transmission, the data in the receive shift register is transferred into the SPIDR and SPIF
remains set (see Figure 12-9).
If SPIF is set and valid data is in the receive shift register, and SPIF is serviced after the start of a
third transmission, the data in the receive shift register has become invalid and is not transferred
into the SPIDR (see Figure 12-10).
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Serial Peripheral Interface (S12SPIV5)
Data A Received
Data B Received
Data C Received
SPIF Serviced
Receive Shift Register
Data B
Data A
Data C
SPIF
SPI Data Register
Data B
Data A
= Unspecified
Data C
= Reception in progress
Figure 12-9. Reception with SPIF serviced in Time
Data A Received
Data B Received
Data C Received
Data B Lost
SPIF Serviced
Receive Shift Register
Data B
Data A
Data C
SPIF
SPI Data Register
Data A
= Unspecified
Data C
= Reception in progress
Figure 12-10. Reception with SPIF serviced too late
12.4
Functional Description
The SPI module allows a duplex, synchronous, serial communication between the MCU and peripheral
devices. Software can poll the SPI status flags or SPI operation can be interrupt driven.
The SPI system is enabled by setting the SPI enable (SPE) bit in SPI control register 1. While SPE is set,
the four associated SPI port pins are dedicated to the SPI function as:
• Slave select (SS)
• Serial clock (SCK)
• Master out/slave in (MOSI)
• Master in/slave out (MISO)
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Serial Peripheral Interface (S12SPIV5)
The main element of the SPI system is the SPI data register. The n-bit1 data register in the master and the
n-bit1 data register in the slave are linked by the MOSI and MISO pins to form a distributed 2n-bit1
register. When a data transfer operation is performed, this 2n-bit1 register is serially shifted n1 bit positions
by the S-clock from the master, so data is exchanged between the master and the slave. Data written to the
master SPI data register becomes the output data for the slave, and data read from the master SPI data
register after a transfer operation is the input data from the slave.
A read of SPISR with SPTEF = 1 followed by a write to SPIDR puts data into the transmit data register.
When a transfer is complete and SPIF is cleared, received data is moved into the receive data register. This
data register acts as the SPI receive data register for reads and as the SPI transmit data register for writes.
A common SPI data register address is shared for reading data from the read data buffer and for writing
data to the transmit data register.
The clock phase control bit (CPHA) and a clock polarity control bit (CPOL) in the SPI control register 1
(SPICR1) select one of four possible clock formats to be used by the SPI system. The CPOL bit simply
selects a non-inverted or inverted clock. The CPHA bit is used to accommodate two fundamentally
different protocols by sampling data on odd numbered SCK edges or on even numbered SCK edges (see
Section 12.4.3, “Transmission Formats”).
The SPI can be configured to operate as a master or as a slave. When the MSTR bit in SPI control register1
is set, master mode is selected, when the MSTR bit is clear, slave mode is selected.
NOTE
A change of CPOL or MSTR bit while there is a received byte pending in
the receive shift register will destroy the received byte and must be avoided.
12.4.1
Master Mode
The SPI operates in master mode when the MSTR bit is set. Only a master SPI module can initiate
transmissions. A transmission begins by writing to the master SPI data register. If the shift register is
empty, data immediately transfers to the shift register. Data begins shifting out on the MOSI pin under the
control of the serial clock.
• Serial clock
The SPR2, SPR1, and SPR0 baud rate selection bits, in conjunction with the SPPR2, SPPR1, and
SPPR0 baud rate preselection bits in the SPI baud rate register, control the baud rate generator and
determine the speed of the transmission. The SCK pin is the SPI clock output. Through the SCK
pin, the baud rate generator of the master controls the shift register of the slave peripheral.
• MOSI, MISO pin
In master mode, the function of the serial data output pin (MOSI) and the serial data input pin
(MISO) is determined by the SPC0 and BIDIROE control bits.
• SS pin
If MODFEN and SSOE are set, the SS pin is configured as slave select output. The SS output
becomes low during each transmission and is high when the SPI is in idle state.
If MODFEN is set and SSOE is cleared, the SS pin is configured as input for detecting mode fault
error. If the SS input becomes low this indicates a mode fault error where another master tries to
1. n depends on the selected transfer width, please refer to Section 12.3.2.2, “SPI Control Register 2 (SPICR2)
S12P-Family Reference Manual, Rev. 1.13
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Serial Peripheral Interface (S12SPIV5)
drive the MOSI and SCK lines. In this case, the SPI immediately switches to slave mode, by
clearing the MSTR bit and also disables the slave output buffer MISO (or SISO in bidirectional
mode). So the result is that all outputs are disabled and SCK, MOSI, and MISO are inputs. If a
transmission is in progress when the mode fault occurs, the transmission is aborted and the SPI is
forced into idle state.
This mode fault error also sets the mode fault (MODF) flag in the SPI status register (SPISR). If
the SPI interrupt enable bit (SPIE) is set when the MODF flag becomes set, then an SPI interrupt
sequence is also requested.
When a write to the SPI data register in the master occurs, there is a half SCK-cycle delay. After
the delay, SCK is started within the master. The rest of the transfer operation differs slightly,
depending on the clock format specified by the SPI clock phase bit, CPHA, in SPI control register 1
(see Section 12.4.3, “Transmission Formats”).
NOTE
A change of the bits CPOL, CPHA, SSOE, LSBFE, XFRW, MODFEN,
SPC0, or BIDIROE with SPC0 set, SPPR2-SPPR0 and SPR2-SPR0 in
master mode will abort a transmission in progress and force the SPI into idle
state. The remote slave cannot detect this, therefore the master must ensure
that the remote slave is returned to idle state.
12.4.2
Slave Mode
The SPI operates in slave mode when the MSTR bit in SPI control register 1 is clear.
• Serial clock
In slave mode, SCK is the SPI clock input from the master.
• MISO, MOSI pin
In slave mode, the function of the serial data output pin (MISO) and serial data input pin (MOSI)
is determined by the SPC0 bit and BIDIROE bit in SPI control register 2.
• SS pin
The SS pin is the slave select input. Before a data transmission occurs, the SS pin of the slave SPI
must be low. SS must remain low until the transmission is complete. If SS goes high, the SPI is
forced into idle state.
The SS input also controls the serial data output pin, if SS is high (not selected), the serial data
output pin is high impedance, and, if SS is low, the first bit in the SPI data register is driven out of
the serial data output pin. Also, if the slave is not selected (SS is high), then the SCK input is
ignored and no internal shifting of the SPI shift register occurs.
Although the SPI is capable of duplex operation, some SPI peripherals are capable of only
receiving SPI data in a slave mode. For these simpler devices, there is no serial data out pin.
NOTE
When peripherals with duplex capability are used, take care not to
simultaneously enable two receivers whose serial outputs drive the same
system slave’s serial data output line.
S12P-Family Reference Manual, Rev. 1.13
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Serial Peripheral Interface (S12SPIV5)
As long as no more than one slave device drives the system slave’s serial data output line, it is possible for
several slaves to receive the same transmission from a master, although the master would not receive return
information from all of the receiving slaves.
If the CPHA bit in SPI control register 1 is clear, odd numbered edges on the SCK input cause the data at
the serial data input pin to be latched. Even numbered edges cause the value previously latched from the
serial data input pin to shift into the LSB or MSB of the SPI shift register, depending on the LSBFE bit.
If the CPHA bit is set, even numbered edges on the SCK input cause the data at the serial data input pin to
be latched. Odd numbered edges cause the value previously latched from the serial data input pin to shift
into the LSB or MSB of the SPI shift register, depending on the LSBFE bit.
When CPHA is set, the first edge is used to get the first data bit onto the serial data output pin. When CPHA
is clear and the SS input is low (slave selected), the first bit of the SPI data is driven out of the serial data
output pin. After the nth1 shift, the transfer is considered complete and the received data is transferred into
the SPI data register. To indicate transfer is complete, the SPIF flag in the SPI status register is set.
NOTE
A change of the bits CPOL, CPHA, SSOE, LSBFE, MODFEN, SPC0, or
BIDIROE with SPC0 set in slave mode will corrupt a transmission in
progress and must be avoided.
12.4.3
Transmission Formats
During an SPI transmission, data is transmitted (shifted out serially) and received (shifted in serially)
simultaneously. The serial clock (SCK) synchronizes shifting and sampling of the information on the two
serial data lines. A slave select line allows selection of an individual slave SPI device; slave devices that
are not selected do not interfere with SPI bus activities. Optionally, on a master SPI device, the slave select
line can be used to indicate multiple-master bus contention.
MASTER SPI
SHIFT REGISTER
BAUD RATE
GENERATOR
SLAVE SPI
MISO
MISO
MOSI
MOSI
SCK
SCK
SS
VDD
SHIFT REGISTER
SS
Figure 12-11. Master/Slave Transfer Block Diagram
12.4.3.1
Clock Phase and Polarity Controls
Using two bits in the SPI control register 1, software selects one of four combinations of serial clock phase
and polarity.
1. n depends on the selected transfer width, please refer to Section 12.3.2.2, “SPI Control Register 2 (SPICR2)
S12P-Family Reference Manual, Rev. 1.13
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Freescale Semiconductor
Serial Peripheral Interface (S12SPIV5)
The CPOL clock polarity control bit specifies an active high or low clock and has no significant effect on
the transmission format.
The CPHA clock phase control bit selects one of two fundamentally different transmission formats.
Clock phase and polarity should be identical for the master SPI device and the communicating slave
device. In some cases, the phase and polarity are changed between transmissions to allow a master device
to communicate with peripheral slaves having different requirements.
12.4.3.2
CPHA = 0 Transfer Format
The first edge on the SCK line is used to clock the first data bit of the slave into the master and the first
data bit of the master into the slave. In some peripherals, the first bit of the slave’s data is available at the
slave’s data out pin as soon as the slave is selected. In this format, the first SCK edge is issued a half cycle
after SS has become low.
A half SCK cycle later, the second edge appears on the SCK line. When this second edge occurs, the value
previously latched from the serial data input pin is shifted into the LSB or MSB of the shift register,
depending on LSBFE bit.
After this second edge, the next bit of the SPI master data is transmitted out of the serial data output pin of
the master to the serial input pin on the slave. This process continues for a total of 16 edges on the SCK
line, with data being latched on odd numbered edges and shifted on even numbered edges.
Data reception is double buffered. Data is shifted serially into the SPI shift register during the transfer and
is transferred to the parallel SPI data register after the last bit is shifted in.
After 2n1 (last) SCK edges:
• Data that was previously in the master SPI data register should now be in the slave data register and
the data that was in the slave data register should be in the master.
• The SPIF flag in the SPI status register is set, indicating that the transfer is complete.
Figure 12-12 is a timing diagram of an SPI transfer where CPHA = 0. SCK waveforms are shown for
CPOL = 0 and CPOL = 1. The diagram may be interpreted as a master or slave timing diagram because
the SCK, MISO, and MOSI pins are connected directly between the master and the slave. The MISO signal
is the output from the slave and the MOSI signal is the output from the master. The SS pin of the master
must be either high or reconfigured as a general-purpose output not affecting the SPI.
1. n depends on the selected transfer width, please refer to Section 12.3.2.2, “SPI Control Register 2 (SPICR2)
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End of Idle State
Begin
1
SCK Edge Number
2
3
4
5
6
7
8
Begin of Idle State
End
Transfer
9
10
11
12
13 14
15
16
Bit 1
Bit 6
LSB Minimum 1/2 SCK
for tT, tl, tL
MSB
SCK (CPOL = 0)
SCK (CPOL = 1)
If next transfer begins here
SAMPLE I
MOSI/MISO
CHANGE O
MOSI pin
CHANGE O
MISO pin
SEL SS (O)
Master only
SEL SS (I)
tT
tL
MSB first (LSBFE = 0): MSB
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
LSB first (LSBFE = 1): LSB
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
tL = Minimum leading time before the first SCK edge
tT = Minimum trailing time after the last SCK edge
tI = Minimum idling time between transfers (minimum SS high time)
tL, tT, and tI are guaranteed for the master mode and required for the slave mode.
tI
tL
Figure 12-12. SPI Clock Format 0 (CPHA = 0), with 8-bit Transfer Width selected (XFRW = 0)
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End of Idle State
SCK Edge Number
Begin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Begin of Idle State
End
Transfer
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
SCK (CPOL = 0)
SCK (CPOL = 1)
If next transfer begins here
SAMPLE I
MOSI/MISO
CHANGE O
MOSI pin
CHANGE O
MISO pin
SEL SS (O)
Master only
SEL SS (I)
MSB first (LSBFE = 0)
LSB first (LSBFE = 1)
tL
tT tI tL
MSB Bit 14Bit 13Bit 12Bit 11 Bit 10 Bit 9 Bit 8 Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 LSB
Minimum 1/2 SCK
LSB Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7 Bit 8 Bit 9 Bit 10Bit 11Bit 12Bit 13Bit 14 MSB
for tT, tl, tL
tL = Minimum leading time before the first SCK edge
tT = Minimum trailing time after the last SCK edge
tI = Minimum idling time between transfers (minimum SS high time)
tL, tT, and tI are guaranteed for the master mode and required for the slave mode.
Figure 12-13. SPI Clock Format 0 (CPHA = 0), with 16-Bit Transfer Width selected (XFRW = 1)
In slave mode, if the SS line is not deasserted between the successive transmissions then the content of the
SPI data register is not transmitted; instead the last received data is transmitted. If the SS line is deasserted
for at least minimum idle time (half SCK cycle) between successive transmissions, then the content of the
SPI data register is transmitted.
In master mode, with slave select output enabled the SS line is always deasserted and reasserted between
successive transfers for at least minimum idle time.
12.4.3.3
CPHA = 1 Transfer Format
Some peripherals require the first SCK edge before the first data bit becomes available at the data out pin,
the second edge clocks data into the system. In this format, the first SCK edge is issued by setting the
CPHA bit at the beginning of the n1-cycle transfer operation.
The first edge of SCK occurs immediately after the half SCK clock cycle synchronization delay. This first
edge commands the slave to transfer its first data bit to the serial data input pin of the master.
A half SCK cycle later, the second edge appears on the SCK pin. This is the latching edge for both the
master and slave.
1. n depends on the selected transfer width, please refer to Section 12.3.2.2, “SPI Control Register 2 (SPICR2)
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When the third edge occurs, the value previously latched from the serial data input pin is shifted into the
LSB or MSB of the SPI shift register, depending on LSBFE bit. After this edge, the next bit of the master
data is coupled out of the serial data output pin of the master to the serial input pin on the slave.
This process continues for a total of n1 edges on the SCK line with data being latched on even numbered
edges and shifting taking place on odd numbered edges.
Data reception is double buffered, data is serially shifted into the SPI shift register during the transfer and
is transferred to the parallel SPI data register after the last bit is shifted in.
After 2n1 SCK edges:
• Data that was previously in the SPI data register of the master is now in the data register of the
slave, and data that was in the data register of the slave is in the master.
• The SPIF flag bit in SPISR is set indicating that the transfer is complete.
Figure 12-14 shows two clocking variations for CPHA = 1. The diagram may be interpreted as a master or
slave timing diagram because the SCK, MISO, and MOSI pins are connected directly between the master
and the slave. The MISO signal is the output from the slave, and the MOSI signal is the output from the
master. The SS line is the slave select input to the slave. The SS pin of the master must be either high or
reconfigured as a general-purpose output not affecting the SPI.
End of Idle State
Begin
SCK Edge Number
1
2
3
4
End
Transfer
5
6
7
8
9
10
11
12
13 14
Begin of Idle State
15
16
SCK (CPOL = 0)
SCK (CPOL = 1)
If next transfer begins here
SAMPLE I
MOSI/MISO
CHANGE O
MOSI pin
CHANGE O
MISO pin
SEL SS (O)
Master only
SEL SS (I)
tT
tL
tI
tL
MSB first (LSBFE = 0):
LSB first (LSBFE = 1):
MSB
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
LSB Minimum 1/2 SCK
for tT, tl, tL
LSB
Bit 1
Bit 2
Bit 3
Bit 4
Bit 5
Bit 6
MSB
tL = Minimum leading time before the first SCK edge, not required for back-to-back transfers
tT = Minimum trailing time after the last SCK edge
tI = Minimum idling time between transfers (minimum SS high time), not required for back-to-back transfers
Figure 12-14. SPI Clock Format 1 (CPHA = 1), with 8-Bit Transfer Width selected (XFRW = 0)
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End of Idle State
SCK Edge Number
Begin
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Begin of Idle State
End
Transfer
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
SCK (CPOL = 0)
SCK (CPOL = 1)
If next transfer begins here
SAMPLE I
MOSI/MISO
CHANGE O
MOSI pin
CHANGE O
MISO pin
SEL SS (O)
Master only
SEL SS (I)
tT tI tL
Minimum 1/2 SCK
for tT, tl, tL
tL
MSB first (LSBFE = 0)
LSB first (LSBFE = 1)
MSB Bit 14Bit 13Bit 12Bit 11 Bit 10 Bit 9 Bit 8 Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 LSB
LSB Bit 1 Bit 2 Bit 3 Bit 4 Bit 5 Bit 6 Bit 7 Bit 8 Bit 9 Bit 10Bit 11Bit 12Bit 13Bit 14 MSB
tL = Minimum leading time before the first SCK edge, not required for back-to-back transfers
tT = Minimum trailing time after the last SCK edge
tI = Minimum idling time between transfers (minimum SS high time), not required for back-to-back transfers
Figure 12-15. SPI Clock Format 1 (CPHA = 1), with 16-Bit Transfer Width selected (XFRW = 1)
The SS line can remain active low between successive transfers (can be tied low at all times). This format
is sometimes preferred in systems having a single fixed master and a single slave that drive the MISO data
line.
• Back-to-back transfers in master mode
In master mode, if a transmission has completed and new data is available in the SPI data register,
this data is sent out immediately without a trailing and minimum idle time.
The SPI interrupt request flag (SPIF) is common to both the master and slave modes. SPIF gets set one
half SCK cycle after the last SCK edge.
12.4.4
SPI Baud Rate Generation
Baud rate generation consists of a series of divider stages. Six bits in the SPI baud rate register (SPPR2,
SPPR1, SPPR0, SPR2, SPR1, and SPR0) determine the divisor to the SPI module clock which results in
the SPI baud rate.
The SPI clock rate is determined by the product of the value in the baud rate preselection bits
(SPPR2–SPPR0) and the value in the baud rate selection bits (SPR2–SPR0). The module clock divisor
equation is shown in Equation 12-3.
BaudRateDivisor = (SPPR + 1) • 2(SPR + 1)
Eqn. 12-3
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When all bits are clear (the default condition), the SPI module clock is divided by 2. When the selection
bits (SPR2–SPR0) are 001 and the preselection bits (SPPR2–SPPR0) are 000, the module clock divisor
becomes 4. When the selection bits are 010, the module clock divisor becomes 8, etc.
When the preselection bits are 001, the divisor determined by the selection bits is multiplied by 2. When
the preselection bits are 010, the divisor is multiplied by 3, etc. See Table 12-7 for baud rate calculations
for all bit conditions, based on a 25 MHz bus clock. The two sets of selects allows the clock to be divided
by a non-power of two to achieve other baud rates such as divide by 6, divide by 10, etc.
The baud rate generator is activated only when the SPI is in master mode and a serial transfer is taking
place. In the other cases, the divider is disabled to decrease IDD current.
NOTE
For maximum allowed baud rates, please refer to the SPI Electrical
Specification in the Electricals chapter of this data sheet.
12.4.5
12.4.5.1
Special Features
SS Output
The SS output feature automatically drives the SS pin low during transmission to select external devices
and drives it high during idle to deselect external devices. When SS output is selected, the SS output pin
is connected to the SS input pin of the external device.
The SS output is available only in master mode during normal SPI operation by asserting SSOE and
MODFEN bit as shown in Table 12-3.
The mode fault feature is disabled while SS output is enabled.
NOTE
Care must be taken when using the SS output feature in a multimaster
system because the mode fault feature is not available for detecting system
errors between masters.
12.4.5.2
Bidirectional Mode (MOMI or SISO)
The bidirectional mode is selected when the SPC0 bit is set in SPI control register 2 (see Table 12-11). In
this mode, the SPI uses only one serial data pin for the interface with external device(s). The MSTR bit
decides which pin to use. The MOSI pin becomes the serial data I/O (MOMI) pin for the master mode, and
the MISO pin becomes serial data I/O (SISO) pin for the slave mode. The MISO pin in master mode and
MOSI pin in slave mode are not used by the SPI.
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Table 12-11. Normal Mode and Bidirectional Mode
When SPE = 1
Master Mode MSTR = 1
Serial Out
Normal Mode
SPC0 = 0
MOSI
MOSI
Serial In
SPI
SPI
Serial In
MISO
Serial Out
Bidirectional Mode
SPC0 = 1
Slave Mode MSTR = 0
MOMI
Serial Out
MISO
Serial In
BIDIROE
SPI
BIDIROE
Serial In
SPI
Serial Out
SISO
The direction of each serial I/O pin depends on the BIDIROE bit. If the pin is configured as an output,
serial data from the shift register is driven out on the pin. The same pin is also the serial input to the shift
register.
• The SCK is output for the master mode and input for the slave mode.
• The SS is the input or output for the master mode, and it is always the input for the slave mode.
• The bidirectional mode does not affect SCK and SS functions.
NOTE
In bidirectional master mode, with mode fault enabled, both data pins MISO
and MOSI can be occupied by the SPI, though MOSI is normally used for
transmissions in bidirectional mode and MISO is not used by the SPI. If a
mode fault occurs, the SPI is automatically switched to slave mode. In this
case MISO becomes occupied by the SPI and MOSI is not used. This must
be considered, if the MISO pin is used for another purpose.
12.4.6
Error Conditions
The SPI has one error condition:
• Mode fault error
12.4.6.1
Mode Fault Error
If the SS input becomes low while the SPI is configured as a master, it indicates a system error where more
than one master may be trying to drive the MOSI and SCK lines simultaneously. This condition is not
permitted in normal operation, the MODF bit in the SPI status register is set automatically, provided the
MODFEN bit is set.
In the special case where the SPI is in master mode and MODFEN bit is cleared, the SS pin is not used by
the SPI. In this special case, the mode fault error function is inhibited and MODF remains cleared. In case
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Serial Peripheral Interface (S12SPIV5)
the SPI system is configured as a slave, the SS pin is a dedicated input pin. Mode fault error doesn’t occur
in slave mode.
If a mode fault error occurs, the SPI is switched to slave mode, with the exception that the slave output
buffer is disabled. So SCK, MISO, and MOSI pins are forced to be high impedance inputs to avoid any
possibility of conflict with another output driver. A transmission in progress is aborted and the SPI is
forced into idle state.
If the mode fault error occurs in the bidirectional mode for a SPI system configured in master mode, output
enable of the MOMI (MOSI in bidirectional mode) is cleared if it was set. No mode fault error occurs in
the bidirectional mode for SPI system configured in slave mode.
The mode fault flag is cleared automatically by a read of the SPI status register (with MODF set) followed
by a write to SPI control register 1. If the mode fault flag is cleared, the SPI becomes a normal master or
slave again.
NOTE
If a mode fault error occurs and a received data byte is pending in the receive
shift register, this data byte will be lost.
12.4.7
12.4.7.1
Low Power Mode Options
SPI in Run Mode
In run mode with the SPI system enable (SPE) bit in the SPI control register clear, the SPI system is in a
low-power, disabled state. SPI registers remain accessible, but clocks to the core of this module are
disabled.
12.4.7.2
SPI in Wait Mode
SPI operation in wait mode depends upon the state of the SPISWAI bit in SPI control register 2.
• If SPISWAI is clear, the SPI operates normally when the CPU is in wait mode
• If SPISWAI is set, SPI clock generation ceases and the SPI module enters a power conservation
state when the CPU is in wait mode.
–
If SPISWAI is set and the SPI is configured for master, any transmission and reception in
progress stops at wait mode entry. The transmission and reception resumes when the SPI exits
wait mode.
–
If SPISWAI is set and the SPI is configured as a slave, any transmission and reception in
progress continues if the SCK continues to be driven from the master. This keeps the slave
synchronized to the master and the SCK.
If the master transmits several bytes while the slave is in wait mode, the slave will continue to
send out bytes consistent with the operation mode at the start of wait mode (i.e., if the slave is
currently sending its SPIDR to the master, it will continue to send the same byte. Else if the
slave is currently sending the last received byte from the master, it will continue to send each
previous master byte).
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NOTE
Care must be taken when expecting data from a master while the slave is in
wait or stop mode. Even though the shift register will continue to operate,
the rest of the SPI is shut down (i.e., a SPIF interrupt will not be generated
until exiting stop or wait mode). Also, the byte from the shift register will
not be copied into the SPIDR register until after the slave SPI has exited wait
or stop mode. In slave mode, a received byte pending in the receive shift
register will be lost when entering wait or stop mode. An SPIF flag and
SPIDR copy is generated only if wait mode is entered or exited during a
tranmission. If the slave enters wait mode in idle mode and exits wait mode
in idle mode, neither a SPIF nor a SPIDR copy will occur.
12.4.7.3
SPI in Stop Mode
Stop mode is dependent on the system. The SPI enters stop mode when the module clock is disabled (held
high or low). If the SPI is in master mode and exchanging data when the CPU enters stop mode, the
transmission is frozen until the CPU exits stop mode. After stop, data to and from the external SPI is
exchanged correctly. In slave mode, the SPI will stay synchronized with the master.
The stop mode is not dependent on the SPISWAI bit.
12.4.7.4
Reset
The reset values of registers and signals are described in Section 12.3, “Memory Map and Register
Definition”, which details the registers and their bit fields.
• If a data transmission occurs in slave mode after reset without a write to SPIDR, it will transmit
garbage, or the data last received from the master before the reset.
• Reading from the SPIDR after reset will always read zeros.
12.4.7.5
Interrupts
The SPI only originates interrupt requests when SPI is enabled (SPE bit in SPICR1 set). The following is
a description of how the SPI makes a request and how the MCU should acknowledge that request. The
interrupt vector offset and interrupt priority are chip dependent.
The interrupt flags MODF, SPIF, and SPTEF are logically ORed to generate an interrupt request.
12.4.7.5.1
MODF
MODF occurs when the master detects an error on the SS pin. The master SPI must be configured for the
MODF feature (see Table 12-3). After MODF is set, the current transfer is aborted and the following bit is
changed:
• MSTR = 0, The master bit in SPICR1 resets.
The MODF interrupt is reflected in the status register MODF flag. Clearing the flag will also clear the
interrupt. This interrupt will stay active while the MODF flag is set. MODF has an automatic clearing
process which is described in Section 12.3.2.4, “SPI Status Register (SPISR)”.
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12.4.7.5.2
SPIF
SPIF occurs when new data has been received and copied to the SPI data register. After SPIF is set, it does
not clear until it is serviced. SPIF has an automatic clearing process, which is described in
Section 12.3.2.4, “SPI Status Register (SPISR)”.
12.4.7.5.3
SPTEF
SPTEF occurs when the SPI data register is ready to accept new data. After SPTEF is set, it does not clear
until it is serviced. SPTEF has an automatic clearing process, which is described in Section 12.3.2.4, “SPI
Status Register (SPISR)”.
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Chapter 13
128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-1. Revision History
Revision
Number
Revision
Date
Sections
Affected
V01.09
28 Jul 2008
13.1.1/13-426
13.3.1/13-429
V01.10
19 Dec 2008
13.1/13-425
13.4.5.4/13-457
13.4.5.6/13-459
13.4.5.11/13463
13.4.5.11/13463
13.4.5.11/13463
13.5.2/13-471
V01.11
25 Sep 2009
-The following changes were made to clarify module behavior related to Flash
register access during reset sequence and while Flash commands are active:
13.3.2/13-432 - Add caution concerning register writes while command is active
13.3.2.1/13-433 - Writes to FCLKDIV are allowed during reset sequence while CCIF is clear
13.4.3.2/13-451 - Add caution concerning register writes while command is active
- Writes to FCCOBIX, FCCOBHI, FCCOBLO registers are ignored during
13.6/13-472
reset sequence
13.1
Description of Changes
- Remove reference to IFRON in Program IFR definition
- Remove reference to IFRON in Table 13-4 and Figure 13-3
- Clarify single bit fault correction for P-Flash phrase
- Add statement concerning code runaway when executing Read Once,
Program Once, and Verify Backdoor Access Key commands from Flash block
containing associated fields
- Relate Key 0 to associated Backdoor Comparison Key address
- Change “power down reset” to “reset”
- Reformat section on unsecuring MCU using BDM
Introduction
The FTMRC128K1 module implements the following:
• 128 Kbytes of P-Flash (Program Flash) memory
• 4 Kbytes of D-Flash (Data Flash) memory
The Flash memory is ideal for single-supply applications allowing for field reprogramming without
requiring external high voltage sources for program or erase operations. The Flash module includes a
memory controller that executes commands to modify Flash memory contents. The user interface to the
memory controller consists of the indexed Flash Common Command Object (FCCOB) register which is
written to with the command, global address, data, and any required command parameters. The memory
controller must complete the execution of a command before the FCCOB register can be written to with a
new command.
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CAUTION
A Flash word or phrase must be in the erased state before being
programmed. Cumulative programming of bits within a Flash word or
phrase is not allowed.
The Flash memory may be read as bytes, aligned words, or misaligned words. Read access time is one bus
cycle for bytes and aligned words, and two bus cycles for misaligned words. For Flash memory, an erased
bit reads 1 and a programmed bit reads 0.
It is possible to read from P-Flash memory while some commands are executing on D-Flash memory. It
is not possible to read from D-Flash memory while a command is executing on P-Flash memory.
Simultaneous P-Flash and D-Flash operations are discussed in Section 13.4.4.
Both P-Flash and D-Flash memories are implemented with Error Correction Codes (ECC) that can resolve
single bit faults and detect double bit faults. For P-Flash memory, the ECC implementation requires that
programming be done on an aligned 8 byte basis (a Flash phrase). Since P-Flash memory is always read
by half-phrase, only one single bit fault in an aligned 4 byte half-phrase containing the byte or word
accessed will be corrected.
13.1.1
Glossary
Command Write Sequence — An MCU instruction sequence to execute built-in algorithms (including
program and erase) on the Flash memory.
D-Flash Memory — The D-Flash memory constitutes the nonvolatile memory store for data.
D-Flash Sector — The D-Flash sector is the smallest portion of the D-Flash memory that can be erased.
The D-Flash sector consists of four 64 byte rows for a total of 256 bytes.
NVM Command Mode — An NVM mode using the CPU to setup the FCCOB register to pass parameters
required for Flash command execution.
Phrase — An aligned group of four 16-bit words within the P-Flash memory. Each phrase includes two
sets of aligned double words with each set including 7 ECC bits for single bit fault correction and double
bit fault detection within each double word.
P-Flash Memory — The P-Flash memory constitutes the main nonvolatile memory store for applications.
P-Flash Sector — The P-Flash sector is the smallest portion of the P-Flash memory that can be erased.
Each P-Flash sector contains 512 bytes.
Program IFR — Nonvolatile information register located in the P-Flash block that contains the Device
ID, Version ID, and the Program Once field.
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128 KByte Flash Module (S12FTMRC128K1V1)
13.1.2
13.1.2.1
•
•
•
•
•
•
•
•
•
•
•
D-Flash Features
4 Kbytes of D-Flash memory composed of one 4 Kbyte Flash block divided into 16 sectors of 256
bytes
Single bit fault correction and double bit fault detection within a word during read operations
Automated program and erase algorithm with verify and generation of ECC parity bits
Fast sector erase and word program operation
Protection scheme to prevent accidental program or erase of D-Flash memory
Ability to program up to four words in a burst sequence
13.1.2.3
•
•
•
P-Flash Features
128 Kbytes of P-Flash memory composed of one 128 Kbyte Flash block divided into 256 sectors
of 512 bytes
Single bit fault correction and double bit fault detection within a 32-bit double word during read
operations
Automated program and erase algorithm with verify and generation of ECC parity bits
Fast sector erase and phrase program operation
Ability to read the P-Flash memory while programming a word in the D-Flash memory
Flexible protection scheme to prevent accidental program or erase of P-Flash memory
13.1.2.2
•
Features
Other Flash Module Features
No external high-voltage power supply required for Flash memory program and erase operations
Interrupt generation on Flash command completion and Flash error detection
Security mechanism to prevent unauthorized access to the Flash memory
13.1.3
Block Diagram
The block diagram of the Flash module is shown in Figure 13-1.
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128 KByte Flash Module (S12FTMRC128K1V1)
Flash
Interface
Command
Interrupt
Request
Error
Interrupt
Request
16bit
internal
bus
Registers
P-Flash
32Kx39
sector 0
sector 1
Protection
sector 255
Security
Bus
Clock
CPU
Clock
Divider FCLK
Memory
Controller
D-Flash
2Kx22
sector 0
sector 1
sector 15
Scratch RAM
384x16
Figure 13-1. FTMRC128K1 Block Diagram
13.2
External Signal Description
The Flash module contains no signals that connect off-chip.
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13.3
Memory Map and Registers
This section describes the memory map and registers for the Flash module. Read data from unimplemented
memory space in the Flash module is undefined. Write access to unimplemented or reserved memory space
in the Flash module will be ignored by the Flash module.
13.3.1
Module Memory Map
The S12 architecture places the P-Flash memory between global addresses 0x2_0000 and 0x3_FFFF as
shown in Table 13-2.The P-Flash memory map is shown in Figure 13-2.
Table 13-2. P-Flash Memory Addressing
Global Address
Size
(Bytes)
0x2_0000 – 0x3_FFFF
128 K
Description
P-Flash Block
Contains Flash Configuration Field
(see Table 13-3)
The FPROT register, described in Section 13.3.2.9, can be set to protect regions in the Flash memory from
accidental program or erase. Three separate memory regions, one growing upward from global address
0x3_8000 in the Flash memory (called the lower region), one growing downward from global address
0x3_FFFF in the Flash memory (called the higher region), and the remaining addresses in the Flash
memory, can be activated for protection. The Flash memory addresses covered by these protectable regions
are shown in the P-Flash memory map. The higher address region is mainly targeted to hold the boot loader
code since it covers the vector space. Default protection settings as well as security information that allows
the MCU to restrict access to the Flash module are stored in the Flash configuration field as described in
Table 13-3.
Table 13-3. Flash Configuration Field
Global Address
Size
(Bytes)
0x3_FF00-0x3_FF07
8
Backdoor Comparison Key
Refer to Section 13.4.5.11, “Verify Backdoor Access Key Command,” and
Section 13.5.1, “Unsecuring the MCU using Backdoor Key Access”
0x3_FF08-0x3_FF0B(1)
4
Reserved
0x3_FF0C1
1
P-Flash Protection byte.
Refer to Section 13.3.2.9, “P-Flash Protection Register (FPROT)”
0x3_FF0D1
1
D-Flash Protection byte.
Refer to Section 13.3.2.10, “D-Flash Protection Register (DFPROT)”
0x3_FF0E1
1
Flash Nonvolatile byte
Refer to Section 13.3.2.16, “Flash Option Register (FOPT)”
Description
Flash Security byte
Refer to Section 13.3.2.2, “Flash Security Register (FSEC)”
1. 0x3FF08-0x3_FF0F form a Flash phrase and must be programmed in a single command write sequence. Each byte in
the 0x3_FF08 - 0x3_FF0B reserved field should be programmed to 0xFF.
0x3_FF0F1
1
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128 KByte Flash Module (S12FTMRC128K1V1)
P-Flash START = 0x2_0000
Flash Protected/Unprotected Region
96 Kbytes
0x3_8000
0x3_8400
0x3_8800
0x3_9000
Protection
Fixed End
Flash Protected/Unprotected Lower Region
1, 2, 4, 8 Kbytes
0x3_A000
Flash Protected/Unprotected Region
8 Kbytes (up to 29 Kbytes)
Protection
Movable End
0x3_C000
Protection
Fixed End
0x3_E000
Flash Protected/Unprotected Higher Region
2, 4, 8, 16 Kbytes
0x3_F000
0x3_F800
P-Flash END = 0x3_FFFF
Flash Configuration Field
16 bytes (0x3_FF00 - 0x3_FF0F)
Figure 13-2. P-Flash Memory Map
Table 13-4. Program IFR Fields
Global Address
Size
(Bytes)
0x0_4000 – 0x0_4007
8
Reserved
0x0_4008 – 0x0_40B5
174
Reserved
0x0_40B6 – 0x0_40B7
2
Field Description
Version ID(1)
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-4. Program IFR Fields
Global Address
Size
(Bytes)
0x0_40B8 – 0x0_40BF
8
Field Description
Reserved
Program Once Field
Refer to Section 13.4.5.6, “Program Once Command”
1. Used to track firmware patch versions, see Section 13.4.2
0x0_40C0 – 0x0_40FF
64
Table 13-5. D-Flash and Memory Controller Resource Fields
Global Address
Size
(Bytes)
0x0_4000 – 0x0_43FF
1,024
Reserved
0x0_4400 – 0x0_53FF
4,096
D-Flash Memory
0x0_5400 – 0x0_57FF
1,024
Reserved
0x0_5800 – 0x0_5AFF
768
0x0_5B00 – 0x0_5FFF
1,280
Reserved
0x0_6000 – 0x0_67FF
2,048
Reserved
0x0_6800 – 0x0_7FFF
1. MMCCTL1 register bit
6,144
Reserved
Description
Memory Controller Scratch RAM (RAMON(1) = 1)
0x0_4000
0x0_40FF
P-Flash IFR 1 Kbyte
D-Flash Start = 0x0_4400
D-Flash Memory
4 Kbytes
D-Flash End = 0x0_53FF
Reserved 1 Kbyte
RAM Start = 0x0_5800
RAM End = 0x0_5AFF
Scratch Ram 768 bytes (RAMON)
Reserved 1280 bytes
0x0_6000
Reserved 2 Kbytes
0x0_6800
Reserved 6 Kbytes
0x0_7FFF
Figure 13-3. D-Flash and Memory Controller Resource Memory Map
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128 KByte Flash Module (S12FTMRC128K1V1)
13.3.2
Register Descriptions
The Flash module contains a set of 20 control and status registers located between Flash module base +
0x0000 and 0x0013. A summary of the Flash module registers is given in Figure 13-4 with detailed
descriptions in the following subsections.
CAUTION
Writes to any Flash register must be avoided while a Flash command is
active (CCIF=0) to prevent corruption of Flash register contents and
adversely affect Memory Controller behavior.
Address
& Name
0x0000
FCLKDIV
0x0001
FSEC
0x0002
FCCOBIX
0x0003
FRSV0
0x0004
FCNFG
0x0005
FERCNFG
0x0006
FSTAT
0x0007
FERSTAT
0x0008
FPROT
0x0009
DFPROT
7
R
6
5
4
3
2
1
0
FDIVLCK
FDIV5
FDIV4
FDIV3
FDIV2
FDIV1
FDIV0
KEYEN1
KEYEN0
RNV5
RNV4
RNV3
RNV2
SEC1
SEC0
0
0
0
0
0
CCOBIX2
CCOBIX1
CCOBIX0
0
0
0
0
0
0
FDFD
FSFD
DFDIE
SFDIE
MGSTAT1
MGSTAT0
DFDIF
SFDIF
FDIVLD
W
R
W
R
W
R
0
0
0
0
0
0
W
R
CCIE
IGNSF
W
R
0
0
0
0
0
0
W
R
0
CCIF
ACCERR
FPVIOL
0
0
MGBUSY
RSVD
0
0
W
R
0
0
W
R
RNV6
FPOPEN
FPHDIS
FPHS1
0
0
FPHS0
FPLDIS
FPLS1
FPLS0
DPS3
DPS2
DPS1
DPS0
W
R
0
DPOPEN
W
Figure 13-4. FTMRC128K1 Register Summary
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128 KByte Flash Module (S12FTMRC128K1V1)
Address
& Name
0x000A
FCCOBHI
0x000B
FCCOBLO
0x000C
FRSV1
0x000D
FRSV2
0x000E
FRSV3
0x000F
FRSV4
0x0010
FOPT
0x0011
FRSV5
0x0012
FRSV6
0x0013
FRSV7
7
6
5
4
3
2
1
0
CCOB15
CCOB14
CCOB13
CCOB12
CCOB11
CCOB10
CCOB9
CCOB8
CCOB7
CCOB6
CCOB5
CCOB4
CCOB3
CCOB2
CCOB1
CCOB0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
NV7
NV6
NV5
NV4
NV3
NV2
NV1
NV0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
= Unimplemented or Reserved
Figure 13-4. FTMRC128K1 Register Summary (continued)
13.3.2.1
Flash Clock Divider Register (FCLKDIV)
The FCLKDIV register is used to control timed events in program and erase algorithms.
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128 KByte Flash Module (S12FTMRC128K1V1)
Offset Module Base + 0x0000
7
R
6
5
4
3
2
1
0
0
0
0
FDIVLD
FDIVLCK
FDIV[5:0]
W
Reset
0
0
0
0
0
= Unimplemented or Reserved
Figure 13-5. Flash Clock Divider Register (FCLKDIV)
All bits in the FCLKDIV register are readable, bit 7 is not writable, bit 6 is write-once-hi and controls the
writability of the FDIV field.
CAUTION
The FCLKDIV register must never be written to while a Flash command is
executing (CCIF=0). The FCLKDIV register is writable during the Flash
reset sequence even though CCIF is clear.
Table 13-6. FCLKDIV Field Descriptions
Field
7
FDIVLD
Description
Clock Divider Loaded
0 FCLKDIV register has not been written since the last reset
1 FCLKDIV register has been written since the last reset
6
FDIVLCK
Clock Divider Locked
0 FDIV field is open for writing
1 FDIV value is locked and cannot be changed. Once the lock bit is set high, only reset can clear this bit and
restore writability to the FDIV field.
5–0
FDIV[5:0]
Clock Divider Bits — FDIV[5:0] must be set to effectively divide BUSCLK down to 1 MHz to control timed events
during Flash program and erase algorithms. Table 13-7 shows recommended values for FDIV[5:0] based on the
BUSCLK frequency. Please refer to Section 13.4.3, “Flash Command Operations,” for more information.
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-7. FDIV values for various BUSCLK Frequencies
BUSCLK Frequency
(MHz)
MIN(1)
MAX(2)
1.0
1.6
1.6
BUSCLK Frequency
(MHz)
FDIV[5:0]
MAX
0x00
16.6
17.6
0x10
2.6
0x01
17.6
18.6
0x11
2.6
3.6
0x02
18.6
19.6
0x12
3.6
4.6
0x03
19.6
20.6
0x13
4.6
5.6
0x04
20.6
21.6
0x14
5.6
6.6
0x05
21.6
22.6
0x15
6.6
7.6
0x06
22.6
23.6
0x16
7.6
8.6
0x07
23.6
24.6
0x17
8.6
9.6
0x08
24.6
25.6
0x18
9.6
10.6
0x09
25.6
26.6
0x19
10.6
11.6
0x0A
26.6
27.6
0x1A
11.6
12.6
0x0B
27.6
28.6
0x1B
12.6
13.6
0x0C
28.6
29.6
0x1C
13.6
14.6
0x0D
29.6
30.6
0x1D
14.6
15.6
0x0E
30.6
31.6
0x1E
31.6
32.6
0x1F
MIN
15.6
16.6
0x0F
1. BUSCLK is Greater Than this value.
2. BUSCLK is Less Than or Equal to this value.
13.3.2.2
FDIV[5:0]
1
2
Flash Security Register (FSEC)
The FSEC register holds all bits associated with the security of the MCU and Flash module.
Offset Module Base + 0x0001
7
R
6
5
4
KEYEN[1:0]
3
2
1
RNV[5:2]
0
SEC[1:0]
W
Reset
F
F
F
F
F
F
F
F
= Unimplemented or Reserved
Figure 13-6. Flash Security Register (FSEC)
All bits in the FSEC register are readable but not writable.
During the reset sequence, the FSEC register is loaded with the contents of the Flash security byte in the
Flash configuration field at global address 0x3_FF0F located in P-Flash memory (see Table 13-3) as
indicated by reset condition F in Figure 13-6. If a double bit fault is detected while reading the P-Flash
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128 KByte Flash Module (S12FTMRC128K1V1)
phrase containing the Flash security byte during the reset sequence, all bits in the FSEC register will be
set to leave the Flash module in a secured state with backdoor key access disabled.
Table 13-8. FSEC Field Descriptions
Field
Description
7–6
Backdoor Key Security Enable Bits — The KEYEN[1:0] bits define the enabling of backdoor key access to the
KEYEN[1:0] Flash module as shown in Table 13-9.
5–2
RNV[5:2}
Reserved Nonvolatile Bits — The RNV bits should remain in the erased state for future enhancements.
1–0
SEC[1:0]
Flash Security Bits — The SEC[1:0] bits define the security state of the MCU as shown in Table 13-10. If the
Flash module is unsecured using backdoor key access, the SEC bits are forced to 10.
Table 13-9. Flash KEYEN States
KEYEN[1:0]
Status of Backdoor Key Access
00
DISABLED
01
DISABLED(1)
10
ENABLED
11
DISABLED
1. Preferred KEYEN state to disable backdoor key access.
Table 13-10. Flash Security States
SEC[1:0]
Status of Security
00
SECURED
01
SECURED(1)
10
UNSECURED
11
SECURED
1. Preferred SEC state to set MCU to secured state.
The security function in the Flash module is described in Section 13.5.
13.3.2.3
Flash CCOB Index Register (FCCOBIX)
The FCCOBIX register is used to index the FCCOB register for Flash memory operations.
Offset Module Base + 0x0002
R
7
6
5
4
3
0
0
0
0
0
2
1
0
CCOBIX[2:0]
W
Reset
0
0
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 13-7. FCCOB Index Register (FCCOBIX)
CCOBIX bits are readable and writable while remaining bits read 0 and are not writable.
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-11. FCCOBIX Field Descriptions
Field
Description
2–0
CCOBIX[1:0]
Common Command Register Index— The CCOBIX bits are used to select which word of the FCCOB register
array is being read or written to. See Section 13.3.2.11, “Flash Common Command Object Register (FCCOB),”
for more details.
13.3.2.4
Flash Reserved0 Register (FRSV0)
This Flash register is reserved for factory testing.
Offset Module Base + 0x000C
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 13-8. Flash Reserved0 Register (FRSV0)
All bits in the FRSV0 register read 0 and are not writable.
13.3.2.5
Flash Configuration Register (FCNFG)
The FCNFG register enables the Flash command complete interrupt and forces ECC faults on Flash array
read access from the CPU.
Offset Module Base + 0x0004
7
R
6
5
0
0
CCIE
4
3
2
0
0
IGNSF
1
0
FDFD
FSFD
0
0
W
Reset
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 13-9. Flash Configuration Register (FCNFG)
CCIE, IGNSF, FDFD, and FSFD bits are readable and writable while remaining bits read 0 and are not
writable.
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-12. FCNFG Field Descriptions
Field
Description
7
CCIE
Command Complete Interrupt Enable — The CCIE bit controls interrupt generation when a Flash command
has completed.
0 Command complete interrupt disabled
1 An interrupt will be requested whenever the CCIF flag in the FSTAT register is set (see Section 13.3.2.7)
4
IGNSF
Ignore Single Bit Fault — The IGNSF controls single bit fault reporting in the FERSTAT register (see
Section 13.3.2.8).
0 All single bit faults detected during array reads are reported
1 Single bit faults detected during array reads are not reported and the single bit fault interrupt will not be
generated
1
FDFD
Force Double Bit Fault Detect — The FDFD bit allows the user to simulate a double bit fault during Flash array
read operations and check the associated interrupt routine. The FDFD bit is cleared by writing a 0 to FDFD. The
FECCR registers will not be updated during the Flash array read operation with FDFD set unless an actual
double bit fault is detected.
0 Flash array read operations will set the DFDIF flag in the FERSTAT register only if a double bit fault is detected
1 Any Flash array read operation will force the DFDIF flag in the FERSTAT register to be set (see
Section 13.3.2.7) and an interrupt will be generated as long as the DFDIE interrupt enable in the FERCNFG
register is set (see Section 13.3.2.6)
0
FSFD
Force Single Bit Fault Detect — The FSFD bit allows the user to simulate a single bit fault during Flash array
read operations and check the associated interrupt routine. The FSFD bit is cleared by writing a 0 to FSFD. The
FECCR registers will not be updated during the Flash array read operation with FSFD set unless an actual single
bit fault is detected.
0 Flash array read operations will set the SFDIF flag in the FERSTAT register only if a single bit fault is detected
1 Flash array read operation will force the SFDIF flag in the FERSTAT register to be set (see Section 13.3.2.7)
and an interrupt will be generated as long as the SFDIE interrupt enable in the FERCNFG register is set (see
Section 13.3.2.6)
13.3.2.6
Flash Error Configuration Register (FERCNFG)
The FERCNFG register enables the Flash error interrupts for the FERSTAT flags.
Offset Module Base + 0x0005
R
7
6
5
4
3
2
0
0
0
0
0
0
1
0
DFDIE
SFDIE
0
0
W
Reset
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 13-10. Flash Error Configuration Register (FERCNFG)
All assigned bits in the FERCNFG register are readable and writable.
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-13. FERCNFG Field Descriptions
Field
Description
1
DFDIE
Double Bit Fault Detect Interrupt Enable — The DFDIE bit controls interrupt generation when a double bit fault
is detected during a Flash block read operation.
0 DFDIF interrupt disabled
1 An interrupt will be requested whenever the DFDIF flag is set (see Section 13.3.2.8)
0
SFDIE
Single Bit Fault Detect Interrupt Enable — The SFDIE bit controls interrupt generation when a single bit fault
is detected during a Flash block read operation.
0 SFDIF interrupt disabled whenever the SFDIF flag is set (see Section 13.3.2.8)
1 An interrupt will be requested whenever the SFDIF flag is set (see Section 13.3.2.8)
13.3.2.7
Flash Status Register (FSTAT)
The FSTAT register reports the operational status of the Flash module.
Offset Module Base + 0x0006
7
6
R
5
4
ACCERR
FPVIOL
0
0
0
CCIF
3
2
MGBUSY
RSVD
0
0
1
0
MGSTAT[1:0]
W
Reset
1
0
0(1)
01
= Unimplemented or Reserved
Figure 13-11. Flash Status Register (FSTAT)
1. Reset value can deviate from the value shown if a double bit fault is detected during the reset sequence (see Section 13.6).
CCIF, ACCERR, and FPVIOL bits are readable and writable, MGBUSY and MGSTAT bits are readable
but not writable, while remaining bits read 0 and are not writable.
Table 13-14. FSTAT Field Descriptions
Field
Description
7
CCIF
Command Complete Interrupt Flag — The CCIF flag indicates that a Flash command has completed. The
CCIF flag is cleared by writing a 1 to CCIF to launch a command and CCIF will stay low until command
completion or command violation.
0 Flash command in progress
1 Flash command has completed
5
ACCERR
Flash Access Error Flag — The ACCERR bit indicates an illegal access has occurred to the Flash memory
caused by either a violation of the command write sequence (see Section 13.4.3.2) or issuing an illegal Flash
command. While ACCERR is set, the CCIF flag cannot be cleared to launch a command. The ACCERR bit is
cleared by writing a 1 to ACCERR. Writing a 0 to the ACCERR bit has no effect on ACCERR.
0 No access error detected
1 Access error detected
4
FPVIOL
Flash Protection Violation Flag —The FPVIOL bit indicates an attempt was made to program or erase an
address in a protected area of P-Flash or D-Flash memory during a command write sequence. The FPVIOL
bit is cleared by writing a 1 to FPVIOL. Writing a 0 to the FPVIOL bit has no effect on FPVIOL. While FPVIOL
is set, it is not possible to launch a command or start a command write sequence.
0 No protection violation detected
1 Protection violation detected
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-14. FSTAT Field Descriptions (continued)
Field
3
MGBUSY
2
RSVD
Description
Memory Controller Busy Flag — The MGBUSY flag reflects the active state of the Memory Controller.
0 Memory Controller is idle
1 Memory Controller is busy executing a Flash command (CCIF = 0)
Reserved Bit — This bit is reserved and always reads 0.
1–0
Memory Controller Command Completion Status Flag — One or more MGSTAT flag bits are set if an error
MGSTAT[1:0] is detected during execution of a Flash command or during the Flash reset sequence. See Section 13.4.5,
“Flash Command Description,” and Section 13.6, “Initialization” for details.
13.3.2.8
Flash Error Status Register (FERSTAT)
The FERSTAT register reflects the error status of internal Flash operations.
Offset Module Base + 0x0007
R
7
6
5
4
3
2
0
0
0
0
0
0
1
0
DFDIF
SFDIF
0
0
W
Reset
0
0
0
0
0
0
= Unimplemented or Reserved
Figure 13-12. Flash Error Status Register (FERSTAT)
All flags in the FERSTAT register are readable and only writable to clear the flag.
Table 13-15. FERSTAT Field Descriptions
Field
Description
1
DFDIF
Double Bit Fault Detect Interrupt Flag — The setting of the DFDIF flag indicates that a double bit fault was
detected in the stored parity and data bits during a Flash array read operation or that a Flash array read operation
was attempted on a Flash block that was under a Flash command operation.(1) The DFDIF flag is cleared by
writing a 1 to DFDIF. Writing a 0 to DFDIF has no effect on DFDIF.
0 No double bit fault detected
1 Double bit fault detected or an invalid Flash array read operation attempted
0
SFDIF
Single Bit Fault Detect Interrupt Flag — With the IGNSF bit in the FCNFG register clear, the SFDIF flag
indicates that a single bit fault was detected in the stored parity and data bits during a Flash array read operation
or that a Flash array read operation was attempted on a Flash block that was under a Flash command operation.1
The SFDIF flag is cleared by writing a 1 to SFDIF. Writing a 0 to SFDIF has no effect on SFDIF.
0 No single bit fault detected
1 Single bit fault detected and corrected or an invalid Flash array read operation attempted
1. The single bit fault and double bit fault flags are mutually exclusive for parity errors (an ECC fault occurrence can be either
single fault or double fault but never both). A simultaneous access collision (read attempted while command running) is
indicated when both SFDIF and DFDIF flags are high.
13.3.2.9
P-Flash Protection Register (FPROT)
The FPROT register defines which P-Flash sectors are protected against program and erase operations.
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128 KByte Flash Module (S12FTMRC128K1V1)
Offset Module Base + 0x0008
7
6
R
5
4
3
2
1
0
RNV6
FPOPEN
FPHDIS
FPHS[1:0]
FPLDIS
FPLS[1:0]
W
Reset
F
F
F
F
F
F
F
F
= Unimplemented or Reserved
Figure 13-13. Flash Protection Register (FPROT)
The (unreserved) bits of the FPROT register are writable with the restriction that the size of the protected
region can only be increased (see Section 13.3.2.9.1, “P-Flash Protection Restrictions,” and Table 13-20).
During the reset sequence, the FPROT register is loaded with the contents of the P-Flash protection byte
in the Flash configuration field at global address 0x3_FF0C located in P-Flash memory (see Table 13-3)
as indicated by reset condition ‘F’ in Figure 13-13. To change the P-Flash protection that will be loaded
during the reset sequence, the upper sector of the P-Flash memory must be unprotected, then the P-Flash
protection byte must be reprogrammed. If a double bit fault is detected while reading the P-Flash phrase
containing the P-Flash protection byte during the reset sequence, the FPOPEN bit will be cleared and
remaining bits in the FPROT register will be set to leave the P-Flash memory fully protected.
Trying to alter data in any protected area in the P-Flash memory will result in a protection violation error
and the FPVIOL bit will be set in the FSTAT register. The block erase of a P-Flash block is not possible
if any of the P-Flash sectors contained in the same P-Flash block are protected.
Table 13-16. FPROT Field Descriptions
Field
Description
7
FPOPEN
Flash Protection Operation Enable — The FPOPEN bit determines the protection function for program or
erase operations as shown in Table 13-17 for the P-Flash block.
0 When FPOPEN is clear, the FPHDIS and FPLDIS bits define unprotected address ranges as specified by the
corresponding FPHS and FPLS bits
1 When FPOPEN is set, the FPHDIS and FPLDIS bits enable protection for the address range specified by the
corresponding FPHS and FPLS bits
6
RNV[6]
Reserved Nonvolatile Bit — The RNV bit should remain in the erased state for future enhancements.
5
FPHDIS
Flash Protection Higher Address Range Disable — The FPHDIS bit determines whether there is a
protected/unprotected area in a specific region of the P-Flash memory ending with global address 0x3_FFFF.
0 Protection/Unprotection enabled
1 Protection/Unprotection disabled
4–3
FPHS[1:0]
Flash Protection Higher Address Size — The FPHS bits determine the size of the protected/unprotected area
in P-Flash memory as shown inTable 13-18. The FPHS bits can only be written to while the FPHDIS bit is set.
2
FPLDIS
Flash Protection Lower Address Range Disable — The FPLDIS bit determines whether there is a
protected/unprotected area in a specific region of the P-Flash memory beginning with global address 0x3_8000.
0 Protection/Unprotection enabled
1 Protection/Unprotection disabled
1–0
FPLS[1:0]
Flash Protection Lower Address Size — The FPLS bits determine the size of the protected/unprotected area
in P-Flash memory as shown in Table 13-19. The FPLS bits can only be written to while the FPLDIS bit is set.
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-17. P-Flash Protection Function
Function(1)
FPOPEN
FPHDIS
FPLDIS
1
1
1
No P-Flash Protection
1
1
0
Protected Low Range
1
0
1
Protected High Range
1
0
0
Protected High and Low Ranges
0
1
1
Full P-Flash Memory Protected
0
1
0
Unprotected Low Range
0
0
1
Unprotected High Range
0
0
0
Unprotected High and Low Ranges
1. For range sizes, refer to Table 13-18 and Table 13-19.
Table 13-18. P-Flash Protection Higher Address Range
FPHS[1:0]
Global Address Range
Protected Size
00
0x3_F800–0x3_FFFF
2 Kbytes
01
0x3_F000–0x3_FFFF
4 Kbytes
10
0x3_E000–0x3_FFFF
8 Kbytes
11
0x3_C000–0x3_FFFF
16 Kbytes
Table 13-19. P-Flash Protection Lower Address Range
FPLS[1:0]
Global Address Range
Protected Size
00
0x3_8000–0x3_83FF
1 Kbyte
01
0x3_8000–0x3_87FF
2 Kbytes
10
0x3_8000–0x3_8FFF
4 Kbytes
11
0x3_8000–0x3_9FFF
8 Kbytes
All possible P-Flash protection scenarios are shown in Figure 13-14. Although the protection scheme is
loaded from the Flash memory at global address 0x3_FF0C during the reset sequence, it can be changed
by the user. The P-Flash protection scheme can be used by applications requiring reprogramming in single
chip mode while providing as much protection as possible if reprogramming is not required.
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FPHDIS = 1
FPLDIS = 1
FPHDIS = 1
FPLDIS = 0
FPHDIS = 0
FPLDIS = 1
FPHDIS = 0
FPLDIS = 0
7
6
5
4
3
2
1
0
Scenario
0x3_8000
0x3_FFFF
Scenario
FPHS[1:0]
FPLS[1:0]
FLASH START
FPOPEN = 1
128 KByte Flash Module (S12FTMRC128K1V1)
FPHS[1:0]
0x3_8000
FPOPEN = 0
FPLS[1:0]
FLASH START
0x3_FFFF
Unprotected region
Protected region with size
defined by FPLS
Protected region
not defined by FPLS, FPHS
Protected region with size
defined by FPHS
Figure 13-14. P-Flash Protection Scenarios
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128 KByte Flash Module (S12FTMRC128K1V1)
13.3.2.9.1
P-Flash Protection Restrictions
The general guideline is that P-Flash protection can only be added and not removed. Table 13-20 specifies
all valid transitions between P-Flash protection scenarios. Any attempt to write an invalid scenario to the
FPROT register will be ignored. The contents of the FPROT register reflect the active protection scenario.
See the FPHS and FPLS bit descriptions for additional restrictions.
Table 13-20. P-Flash Protection Scenario Transitions
To Protection Scenario(1)
From
Protection
Scenario
0
1
2
3
0
X
X
X
X
X
1
X
4
X
X
X
X
X
X
X
X
6
6
7
X
3
5
5
X
X
2
4
X
X
X
X
X
X
X
X
X
X
7
1. Allowed transitions marked with X, see Figure 13-14 for a definition of the scenarios.
13.3.2.10 D-Flash Protection Register (DFPROT)
The DFPROT register defines which D-Flash sectors are protected against program and erase operations.
Offset Module Base + 0x0009
7
R
6
5
4
0
0
0
3
2
DPOPEN
1
0
F
F
DPS[3:0]
W
Reset
F
0
0
0
F
F
= Unimplemented or Reserved
Figure 13-15. D-Flash Protection Register (DFPROT)
The (unreserved) bits of the DFPROT register are writable with the restriction that protection can be added
but not removed. Writes must increase the DPS value and the DPOPEN bit can only be written from 1
(protection disabled) to 0 (protection enabled). If the DPOPEN bit is set, the state of the DPS bits is
irrelevant.
During the reset sequence, the DFPROT register is loaded with the contents of the D-Flash protection byte
in the Flash configuration field at global address 0x3_FF0D located in P-Flash memory (see Table 13-3)
as indicated by reset condition F in Figure 13-15. To change the D-Flash protection that will be loaded
during the reset sequence, the P-Flash sector containing the D-Flash protection byte must be unprotected,
then the D-Flash protection byte must be programmed. If a double bit fault is detected while reading the
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128 KByte Flash Module (S12FTMRC128K1V1)
P-Flash phrase containing the D-Flash protection byte during the reset sequence, the DPOPEN bit will be
cleared and DPS bits will be set to leave the D-Flash memory fully protected.
Trying to alter data in any protected area in the D-Flash memory will result in a protection violation error
and the FPVIOL bit will be set in the FSTAT register. Block erase of the D-Flash memory is not possible
if any of the D-Flash sectors are protected.
Table 13-21. DFPROT Field Descriptions
Field
Description
7
DPOPEN
D-Flash Protection Control
0 Enables D-Flash memory protection from program and erase with protected address range defined by DPS
bits
1 Disables D-Flash memory protection from program and erase
3–0
DPS[3:0]
D-Flash Protection Size — The DPS[3:0] bits determine the size of the protected area in the D-Flash memory
as shown in Table 13-22.
Table 13-22. D-Flash Protection Address Range
DPS[3:0]
Global Address Range
Protected Size
0000
0x0_4400 – 0x0_44FF
256 bytes
0001
0x0_4400 – 0x0_45FF
512 bytes
0010
0x0_4400 – 0x0_46FF
768 bytes
0011
0x0_4400 – 0x0_47FF
1024 bytes
0100
0x0_4400 – 0x0_48FF
1280 bytes
0101
0x0_4400 – 0x0_49FF
1536 bytes
0110
0x0_4400 – 0x0_4AFF
1792 bytes
0111
0x0_4400 – 0x0_4BFF
2048 bytes
1000
0x0_4400 – 0x0_4CFF
2304 bytes
1001
0x0_4400 – 0x0_4DFF
2560 bytes
1010
0x0_4400 – 0x0_4EFF
2816 bytes
1011
0x0_4400 – 0x0_4FFF
3072 bytes
1100
0x0_4400 – 0x0_50FF
3328 bytes
1101
0x0_4400 – 0x0_51FF
3584 bytes
1110
0x0_4400 – 0x0_52FF
3840 bytes
1111
0x0_4400 – 0x0_53FF
4096 bytes
13.3.2.11 Flash Common Command Object Register (FCCOB)
The FCCOB is an array of six words addressed via the CCOBIX index found in the FCCOBIX register.
Byte wide reads and writes are allowed to the FCCOB register.
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128 KByte Flash Module (S12FTMRC128K1V1)
Offset Module Base + 0x000A
7
6
5
4
3
2
1
0
0
0
0
0
R
CCOB[15:8]
W
Reset
0
0
0
0
Figure 13-16. Flash Common Command Object High Register (FCCOBHI)
Offset Module Base + 0x000B
7
6
5
4
3
2
1
0
0
0
0
0
R
CCOB[7:0]
W
Reset
0
0
0
0
Figure 13-17. Flash Common Command Object Low Register (FCCOBLO)
13.3.2.11.1 FCCOB - NVM Command Mode
NVM command mode uses the indexed FCCOB register to provide a command code and its relevant
parameters to the Memory Controller. The user first sets up all required FCCOB fields and then initiates
the command’s execution by writing a 1 to the CCIF bit in the FSTAT register (a 1 written by the user
clears the CCIF command completion flag to 0). When the user clears the CCIF bit in the FSTAT register
all FCCOB parameter fields are locked and cannot be changed by the user until the command completes
(as evidenced by the Memory Controller returning CCIF to 1). Some commands return information to the
FCCOB register array.
The generic format for the FCCOB parameter fields in NVM command mode is shown in Table 13-23.
The return values are available for reading after the CCIF flag in the FSTAT register has been returned to
1 by the Memory Controller. Writes to the unimplemented parameter fields (CCOBIX = 110 and CCOBIX
= 111) are ignored with reads from these fields returning 0x0000.
Table 13-23 shows the generic Flash command format. The high byte of the first word in the CCOB array
contains the command code, followed by the parameters for this specific Flash command. For details on
the FCCOB settings required by each command, see the Flash command descriptions in Section 13.4.5.
Table 13-23. FCCOB - NVM Command Mode (Typical Usage)
CCOBIX[2:0]
Byte
FCCOB Parameter Fields (NVM Command Mode)
HI
FCMD[7:0] defining Flash command
LO
6’h0, Global address [17:16]
HI
Global address [15:8]
LO
Global address [7:0]
HI
Data 0 [15:8]
LO
Data 0 [7:0]
000
001
010
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-23. FCCOB - NVM Command Mode (Typical Usage)
CCOBIX[2:0]
Byte
FCCOB Parameter Fields (NVM Command Mode)
HI
Data 1 [15:8]
LO
Data 1 [7:0]
HI
Data 2 [15:8]
LO
Data 2 [7:0]
HI
Data 3 [15:8]
LO
Data 3 [7:0]
011
100
101
13.3.2.12 Flash Reserved1 Register (FRSV1)
This Flash register is reserved for factory testing.
Offset Module Base + 0x000C
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 13-18. Flash Reserved1 Register (FRSV1)
All bits in the FRSV1 register read 0 and are not writable.
13.3.2.13 Flash Reserved2 Register (FRSV2)
This Flash register is reserved for factory testing.
Offset Module Base + 0x000D
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 13-19. Flash Reserved2 Register (FRSV2)
All bits in the FRSV2 register read 0 and are not writable.
13.3.2.14 Flash Reserved3 Register (FRSV3)
This Flash register is reserved for factory testing.
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128 KByte Flash Module (S12FTMRC128K1V1)
Offset Module Base + 0x000E
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 13-20. Flash Reserved3 Register (FRSV3)
All bits in the FRSV3 register read 0 and are not writable.
13.3.2.15 Flash Reserved4 Register (FRSV4)
This Flash register is reserved for factory testing.
Offset Module Base + 0x000F
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 13-21. Flash Reserved4 Register (FRSV4)
All bits in the FRSV4 register read 0 and are not writable.
13.3.2.16 Flash Option Register (FOPT)
The FOPT register is the Flash option register.
Offset Module Base + 0x0010
7
6
5
4
R
3
2
1
0
F
F
F
F
NV[7:0]
W
Reset
F
F
F
F
= Unimplemented or Reserved
Figure 13-22. Flash Option Register (FOPT)
All bits in the FOPT register are readable but are not writable.
During the reset sequence, the FOPT register is loaded from the Flash nonvolatile byte in the Flash
configuration field at global address 0x3_FF0E located in P-Flash memory (see Table 13-3) as indicated
by reset condition F in Figure 13-22. If a double bit fault is detected while reading the P-Flash phrase
containing the Flash nonvolatile byte during the reset sequence, all bits in the FOPT register will be set.
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-24. FOPT Field Descriptions
Field
Description
7–0
NV[7:0]
Nonvolatile Bits — The NV[7:0] bits are available as nonvolatile bits. Refer to the device user guide for proper
use of the NV bits.
13.3.2.17 Flash Reserved5 Register (FRSV5)
This Flash register is reserved for factory testing.
Offset Module Base + 0x0011
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 13-23. Flash Reserved5 Register (FRSV5)
All bits in the FRSV5 register read 0 and are not writable.
13.3.2.18 Flash Reserved6 Register (FRSV6)
This Flash register is reserved for factory testing.
Offset Module Base + 0x0012
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 13-24. Flash Reserved6 Register (FRSV6)
All bits in the FRSV6 register read 0 and are not writable.
13.3.2.19 Flash Reserved7 Register (FRSV7)
This Flash register is reserved for factory testing.
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128 KByte Flash Module (S12FTMRC128K1V1)
Offset Module Base + 0x0013
R
7
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 13-25. Flash Reserved7 Register (FRSV7)
All bits in the FRSV7 register read 0 and are not writable.
13.4
Functional Description
13.4.1
Modes of Operation
The FTMRC128K1 module provides the modes of operation shown in Table 13-25. The operating mode
is determined by module-level inputs and affects the FCLKDIV, FCNFG, and DFPROT registers, Scratch
RAM writes, and the command set availability (see Table 13-27).
Table 13-25. Modes and Mode Control Inputs
Operating
Mode
13.4.2
FTMRC Input
mmc_mode_ss_t2
Normal:
0
Special:
1
IFR Version ID Word
The version ID word is stored in the IFR at address 0x0_40B6. The contents of the word are defined in
Table 13-26.
Table 13-26. IFR Version ID Fields
•
[15:4]
[3:0]
Reserved
VERNUM
VERNUM: Version number. The first version is number 0b_0001 with both 0b_0000 and 0b_1111
meaning ‘none’.
13.4.3
Flash Command Operations
Flash command operations are used to modify Flash memory contents.
The next sections describe:
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Freescale Semiconductor
128 KByte Flash Module (S12FTMRC128K1V1)
•
•
•
How to write the FCLKDIV register that is used to generate a time base (FCLK) derived from
BUSCLK for Flash program and erase command operations
The command write sequence used to set Flash command parameters and launch execution
Valid Flash commands available for execution
13.4.3.1
Writing the FCLKDIV Register
Prior to issuing any Flash program or erase command after a reset, the user is required to write the
FCLKDIV register to divide BUSCLK down to a target FCLK of 1 MHz. Table 13-7 shows recommended
values for the FDIV field based on BUSCLK frequency.
NOTE
Programming or erasing the Flash memory cannot be performed if the bus
clock runs at less than 0.8 MHz. Setting FDIV too high can destroy the Flash
memory due to overstress. Setting FDIV too low can result in incomplete
programming or erasure of the Flash memory cells.
When the FCLKDIV register is written, the FDIVLD bit is set automatically. If the FDIVLD bit is 0, the
FCLKDIV register has not been written since the last reset. If the FCLKDIV register has not been written,
any Flash program or erase command loaded during a command write sequence will not execute and the
ACCERR bit in the FSTAT register will set.
13.4.3.2
Command Write Sequence
The Memory Controller will launch all valid Flash commands entered using a command write sequence.
Before launching a command, the ACCERR and FPVIOL bits in the FSTAT register must be clear (see
Section 13.3.2.7) and the CCIF flag should be tested to determine the status of the current command write
sequence. If CCIF is 0, the previous command write sequence is still active, a new command write
sequence cannot be started, and all writes to the FCCOB register are ignored.
CAUTION
Writes to any Flash register must be avoided while a Flash command is
active (CCIF=0) to prevent corruption of Flash register contents and
Memory Controller behavior.
13.4.3.2.1
Define FCCOB Contents
The FCCOB parameter fields must be loaded with all required parameters for the Flash command being
executed. Access to the FCCOB parameter fields is controlled via the CCOBIX bits in the FCCOBIX
register (see Section 13.3.2.3).
The contents of the FCCOB parameter fields are transferred to the Memory Controller when the user clears
the CCIF command completion flag in the FSTAT register (writing 1 clears the CCIF to 0). The CCIF flag
will remain clear until the Flash command has completed. Upon completion, the Memory Controller will
return CCIF to 1 and the FCCOB register will be used to communicate any results. The flow for a generic
command write sequence is shown in Figure 13-26.
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128 KByte Flash Module (S12FTMRC128K1V1)
START
Read: FCLKDIV register
Clock Divider
Value Check
FDIV
Correct?
no
no
CCIF
Set?
Read: FSTAT register
yes
FCCOB
Availability Check
yes
Read: FSTAT register
Note: FCLKDIV must be
set after each reset
Write: FCLKDIV register
no
CCIF
Set?
yes
Results from previous Command
ACCERR/
FPVIOL
Set?
no
Access Error and
Protection Violation
Check
yes
Write: FSTAT register
Clear ACCERR/FPVIOL 0x30
Write to FCCOBIX register
to identify specific command
parameter to load.
Write to FCCOB register
to load required command parameter.
More
Parameters?
yes
no
Write: FSTAT register (to launch command)
Clear CCIF 0x80
Read: FSTAT register
Bit Polling for
Command Completion
Check
CCIF Set?
no
yes
EXIT
Figure 13-26. Generic Flash Command Write Sequence Flowchart
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Freescale Semiconductor
128 KByte Flash Module (S12FTMRC128K1V1)
13.4.3.3
Valid Flash Module Commands
Table 13-27. Flash Commands by Mode
Unsecured
FCMD
Command
NS
SS(2)
NS
(1)
(3)
SS(4)
0x01
Erase Verify All Blocks
∗
∗
∗
∗
0x02
Erase Verify Block
∗
∗
∗
∗
0x03
Erase Verify P-Flash Section
∗
∗
∗
0x04
Read Once
∗
∗
∗
0x06
Program P-Flash
∗
∗
∗
0x07
Program Once
∗
∗
∗
0x08
Erase All Blocks
0x09
Erase Flash Block
∗
∗
∗
0x0A
Erase P-Flash Sector
∗
∗
∗
0x0B
Unsecure Flash
0x0C
Verify Backdoor Access Key
∗
0x0D
Set User Margin Level
∗
0x0E
Set Field Margin Level
0x10
Erase Verify D-Flash Section
∗
∗
∗
0x11
Program D-Flash
∗
∗
∗
∗
∗
∗
∗
∗
∗
∗
∗
∗
∗
∗
0x12
Erase D-Flash Sector
1. Unsecured Normal Single Chip mode.
2. Unsecured Special Single Chip mode.
3. Secured Normal Single Chip mode.
4. Secured Special Single Chip mode.
13.4.3.4
Secured
P-Flash Commands
Table 13-28 summarizes the valid P-Flash commands along with the effects of the commands on the PFlash block and other resources within the Flash module.
Table 13-28. P-Flash Commands
FCMD
Command
0x01
Erase Verify All
Blocks
0x02
Erase Verify Block
0x03
Erase Verify PFlash Section
Function on P-Flash Memory
Verify that all P-Flash (and D-Flash) blocks are erased.
Verify that a P-Flash block is erased.
Verify that a given number of words starting at the address provided are erased.
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-28. P-Flash Commands
FCMD
Command
Function on P-Flash Memory
0x04
Read Once
Read a dedicated 64 byte field in the nonvolatile information register in P-Flash block that
was previously programmed using the Program Once command.
0x06
Program P-Flash
0x07
Program Once
Program a dedicated 64 byte field in the nonvolatile information register in P-Flash block
that is allowed to be programmed only once.
0x08
Erase All Blocks
Erase all P-Flash (and D-Flash) blocks.
An erase of all Flash blocks is only possible when the FPLDIS, FPHDIS, and FPOPEN
bits in the FPROT register and the DPOPEN bit in the DFPROT register are set prior to
launching the command.
0x09
Erase Flash Block
Erase a P-Flash (or D-Flash) block.
An erase of the full P-Flash block is only possible when FPLDIS, FPHDIS and FPOPEN
bits in the FPROT register are set prior to launching the command.
0x0A
Erase P-Flash
Sector
0x0B
Unsecure Flash
0x0C
Verify Backdoor
Access Key
Supports a method of releasing MCU security by verifying a set of security keys.
0x0D
Set User Margin
Level
Specifies a user margin read level for all P-Flash blocks.
0x0E
Set Field Margin
Level
Specifies a field margin read level for all P-Flash blocks (special modes only).
13.4.3.5
Program a phrase in a P-Flash block.
Erase all bytes in a P-Flash sector.
Supports a method of releasing MCU security by erasing all P-Flash (and D-Flash) blocks
and verifying that all P-Flash (and D-Flash) blocks are erased.
D-Flash Commands
Table 13-29 summarizes the valid D-Flash commands along with the effects of the commands on the DFlash block.
Table 13-29. D-Flash Commands
FCMD
Command
0x01
Erase Verify All
Blocks
0x02
Erase Verify Block
Function on D-Flash Memory
Verify that all D-Flash (and P-Flash) blocks are erased.
Verify that the D-Flash block is erased.
Erase all D-Flash (and P-Flash) blocks.
An erase of all Flash blocks is only possible when the FPLDIS, FPHDIS, and FPOPEN
bits in the FPROT register and the DPOPEN bit in the DFPROT register are set prior to
launching the command.
0x08
Erase All Blocks
0x09
Erase Flash Block
0x0B
Unsecure Flash
0x0D
Set User Margin
Level
Specifies a user margin read level for the D-Flash block.
0x0E
Set Field Margin
Level
Specifies a field margin read level for the D-Flash block (special modes only).
Erase a D-Flash (or P-Flash) block.
An erase of the full D-Flash block is only possible when DPOPEN bit in the DFPROT
register is set prior to launching the command.
Supports a method of releasing MCU security by erasing all D-Flash (and P-Flash) blocks
and verifying that all D-Flash (and P-Flash) blocks are erased.
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-29. D-Flash Commands
FCMD
Command
0x10
Erase Verify DFlash Section
0x11
Program D-Flash
Program up to four words in the D-Flash block.
0x12
Erase D-Flash
Sector
Erase all bytes in a sector of the D-Flash block.
13.4.4
Function on D-Flash Memory
Verify that a given number of words starting at the address provided are erased.
Allowed Simultaneous P-Flash and D-Flash Operations
Only the operations marked ‘OK’ in Table 13-30 are permitted to be run simultaneously on the Program
Flash and Data Flash blocks. Some operations cannot be executed simultaneously because certain
hardware resources are shared by the two memories. The priority has been placed on permitting Program
Flash reads while program and erase operations execute on the Data Flash, providing read (P-Flash) while
write (D-Flash) functionality.
Table 13-30. Allowed P-Flash and D-Flash Simultaneous Operations
Data Flash
Margin
Read1
Program
Sector
Erase
Read
OK
OK
OK
Margin Read(1)
OK(2)
Program Flash
Read
Mass
Erase3
Program
Sector Erase
OK
OK
Mass Erase(3)
1. A ‘Margin Read’ is any read after executing the margin setting commands ‘Set
User Margin Level’ or ‘Set Field Margin Level’ with anything but the ‘normal’
level specified.
2. See the Note on margin settings in Section 13.4.5.12 and Section 13.4.5.13.
3. The ‘Mass Erase’ operations are commands ‘Erase All Blocks’ and ‘Erase
Flash Block’
13.4.5
Flash Command Description
This section provides details of all available Flash commands launched by a command write sequence. The
ACCERR bit in the FSTAT register will be set during the command write sequence if any of the following
illegal steps are performed, causing the command not to be processed by the Memory Controller:
• Starting any command write sequence that programs or erases Flash memory before initializing the
FCLKDIV register
• Writing an invalid command as part of the command write sequence
• For additional possible errors, refer to the error handling table provided for each command
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128 KByte Flash Module (S12FTMRC128K1V1)
If a Flash block is read during execution of an algorithm (CCIF = 0) on that same block, the read operation
will return invalid data. If the SFDIF or DFDIF flags were not previously set when the invalid read
operation occurred, both the SFDIF and DFDIF flags will be set.
If the ACCERR or FPVIOL bits are set in the FSTAT register, the user must clear these bits before starting
any command write sequence (see Section 13.3.2.7).
CAUTION
A Flash word or phrase must be in the erased state before being
programmed. Cumulative programming of bits within a Flash word or
phrase is not allowed.
13.4.5.1
Erase Verify All Blocks Command
The Erase Verify All Blocks command will verify that all P-Flash and D-Flash blocks have been erased.
Table 13-31. Erase Verify All Blocks Command FCCOB Requirements
CCOBIX[2:0]
FCCOB Parameters
000
0x01
Not required
Upon clearing CCIF to launch the Erase Verify All Blocks command, the Memory Controller will verify
that the entire Flash memory space is erased. The CCIF flag will set after the Erase Verify All Blocks
operation has completed.
Table 13-32. Erase Verify All Blocks Command Error Handling
Register
Error Bit
ACCERR
FPVIOL
Error Condition
Set if CCOBIX[2:0] != 000 at command launch
None
FSTAT
13.4.5.2
MGSTAT1
Set if any errors have been encountered during the read
MGSTAT0
Set if any non-correctable errors have been encountered during the read
Erase Verify Block Command
The Erase Verify Block command allows the user to verify that an entire P-Flash or D-Flash block has been
erased. The FCCOB upper global address bits determine which block must be verified.
Table 13-33. Erase Verify Block Command FCCOB Requirements
CCOBIX[2:0]
000
FCCOB Parameters
0x02
Global address [17:16] of the
Flash block to be verified.
Upon clearing CCIF to launch the Erase Verify Block command, the Memory Controller will verify that
the selected P-Flash or D-Flash block is erased. The CCIF flag will set after the Erase Verify Block
operation has completed.
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Table 13-34. Erase Verify Block Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 000 at command launch
ACCERR
Set if an invalid global address [17:16] is supplied
FSTAT
13.4.5.3
FPVIOL
None
MGSTAT1
Set if any errors have been encountered during the read
MGSTAT0
Set if any non-correctable errors have been encountered during the read
Erase Verify P-Flash Section Command
The Erase Verify P-Flash Section command will verify that a section of code in the P-Flash memory is
erased. The Erase Verify P-Flash Section command defines the starting point of the code to be verified and
the number of phrases.
Table 13-35. Erase Verify P-Flash Section Command FCCOB Requirements
CCOBIX[2:0]
FCCOB Parameters
000
0x03
Global address [17:16] of
a P-Flash block
001
Global address [15:0] of the first phrase to be verified
010
Number of phrases to be verified
Upon clearing CCIF to launch the Erase Verify P-Flash Section command, the Memory Controller will
verify the selected section of Flash memory is erased. The CCIF flag will set after the Erase Verify P-Flash
Section operation has completed.
Table 13-36. Erase Verify P-Flash Section Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 010 at command launch
Set if command not available in current mode (see Table 13-27)
ACCERR
Set if an invalid global address [17:0] is supplied
Set if a misaligned phrase address is supplied (global address [2:0] != 000)
FSTAT
Set if the requested section crosses a 128 Kbyte boundary
FPVIOL
13.4.5.4
None
MGSTAT1
Set if any errors have been encountered during the read
MGSTAT0
Set if any non-correctable errors have been encountered during the read
Read Once Command
The Read Once command provides read access to a reserved 64 byte field (8 phrases) located in the
nonvolatile information register of P-Flash. The Read Once field is programmed using the Program Once
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command described in Section 13.4.5.6. The Read Once command must not be executed from the Flash
block containing the Program Once reserved field to avoid code runaway.
Table 13-37. Read Once Command FCCOB Requirements
CCOBIX[2:0]
FCCOB Parameters
000
0x04
Not Required
001
Read Once phrase index (0x0000 - 0x0007)
010
Read Once word 0 value
011
Read Once word 1 value
100
Read Once word 2 value
101
Read Once word 3 value
Upon clearing CCIF to launch the Read Once command, a Read Once phrase is fetched and stored in the
FCCOB indexed register. The CCIF flag will set after the Read Once operation has completed. Valid
phrase index values for the Read Once command range from 0x0000 to 0x0007. During execution of the
Read Once command, any attempt to read addresses within P-Flash block will return invalid data.
8
Table 13-38. Read Once Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 001 at command launch
ACCERR
Set if command not available in current mode (see Table 13-27)
Set if an invalid phrase index is supplied
FSTAT
FPVIOL
13.4.5.5
None
MGSTAT1
Set if any errors have been encountered during the read
MGSTAT0
Set if any non-correctable errors have been encountered during the read
Program P-Flash Command
The Program P-Flash operation will program a previously erased phrase in the P-Flash memory using an
embedded algorithm.
CAUTION
A P-Flash phrase must be in the erased state before being programmed.
Cumulative programming of bits within a Flash phrase is not allowed.
Table 13-39. Program P-Flash Command FCCOB Requirements
CCOBIX[2:0]
000
FCCOB Parameters
0x06
Global address [17:16] to
identify P-Flash block
001
Global address [15:0] of phrase location to be programmed(1)
010
Word 0 program value
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Table 13-39. Program P-Flash Command FCCOB Requirements
CCOBIX[2:0]
FCCOB Parameters
011
Word 1 program value
100
Word 2 program value
101
Word 3 program value
1. Global address [2:0] must be 000
Upon clearing CCIF to launch the Program P-Flash command, the Memory Controller will program the
data words to the supplied global address and will then proceed to verify the data words read back as
expected. The CCIF flag will set after the Program P-Flash operation has completed.
Table 13-40. Program P-Flash Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 101 at command launch
Set if command not available in current mode (see Table 13-27)
ACCERR
Set if an invalid global address [17:0] is supplied
Set if a misaligned phrase address is supplied (global address [2:0] != 000)
FSTAT
FPVIOL
13.4.5.6
Set if the global address [17:0] points to a protected area
MGSTAT1
Set if any errors have been encountered during the verify operation
MGSTAT0
Set if any non-correctable errors have been encountered during the verify
operation
Program Once Command
The Program Once command restricts programming to a reserved 64 byte field (8 phrases) in the
nonvolatile information register located in P-Flash. The Program Once reserved field can be read using the
Read Once command as described in Section 13.4.5.4. The Program Once command must only be issued
once since the nonvolatile information register in P-Flash cannot be erased. The Program Once command
must not be executed from the Flash block containing the Program Once reserved field to avoid code
runaway.
Table 13-41. Program Once Command FCCOB Requirements
CCOBIX[2:0]
000
FCCOB Parameters
0x07
Not Required
001
Program Once phrase index (0x0000 - 0x0007)
010
Program Once word 0 value
011
Program Once word 1 value
100
Program Once word 2 value
101
Program Once word 3 value
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128 KByte Flash Module (S12FTMRC128K1V1)
Upon clearing CCIF to launch the Program Once command, the Memory Controller first verifies that the
selected phrase is erased. If erased, then the selected phrase will be programmed and then verified with
read back. The CCIF flag will remain clear, setting only after the Program Once operation has completed.
The reserved nonvolatile information register accessed by the Program Once command cannot be erased
and any attempt to program one of these phrases a second time will not be allowed. Valid phrase index
values for the Program Once command range from 0x0000 to 0x0007. During execution of the Program
Once command, any attempt to read addresses within P-Flash will return invalid data.
Table 13-42. Program Once Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 101 at command launch
Set if command not available in current mode (see Table 13-27)
ACCERR
Set if an invalid phrase index is supplied
Set if the requested phrase has already been programmed(1)
FSTAT
FPVIOL
MGSTAT1
None
Set if any errors have been encountered during the verify operation
Set if any non-correctable errors have been encountered during the verify
operation
1. If a Program Once phrase is initially programmed to 0xFFFF_FFFF_FFFF_FFFF, the Program Once command will
be allowed to execute again on that same phrase.
MGSTAT0
13.4.5.7
Erase All Blocks Command
The Erase All Blocks operation will erase the entire P-Flash and D-Flash memory space.
Table 13-43. Erase All Blocks Command FCCOB Requirements
CCOBIX[2:0]
000
FCCOB Parameters
0x08
Not required
Upon clearing CCIF to launch the Erase All Blocks command, the Memory Controller will erase the entire
Flash memory space and verify that it is erased. If the Memory Controller verifies that the entire Flash
memory space was properly erased, security will be released. During the execution of this command
(CCIF=0) the user must not write to any Flash module register. The CCIF flag will set after the Erase All
Blocks operation has completed.
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Table 13-44. Erase All Blocks Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 000 at command launch
ACCERR
Set if command not available in current mode (see Table 13-27)
FPVIOL
FSTAT
13.4.5.8
Set if any area of the P-Flash or D-Flash memory is protected
MGSTAT1
Set if any errors have been encountered during the verify operation
MGSTAT0
Set if any non-correctable errors have been encountered during the verify
operation
Erase Flash Block Command
The Erase Flash Block operation will erase all addresses in a P-Flash or D-Flash block.
Table 13-45. Erase Flash Block Command FCCOB Requirements
CCOBIX[2:0]
000
001
FCCOB Parameters
0x09
Global address [17:16] to
identify Flash block
Global address [15:0] in Flash block to be erased
Upon clearing CCIF to launch the Erase Flash Block command, the Memory Controller will erase the
selected Flash block and verify that it is erased. The CCIF flag will set after the Erase Flash Block
operation has completed.
Table 13-46. Erase Flash Block Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 001 at command launch
Set if command not available in current mode (see Table 13-27)
ACCERR
Set if the supplied P-Flash address is not phrase-aligned or if the D-Flash
address is not word-aligned
FSTAT
FPVIOL
13.4.5.9
Set if an invalid global address [17:16] is supplied
Set if an area of the selected Flash block is protected
MGSTAT1
Set if any errors have been encountered during the verify operation
MGSTAT0
Set if any non-correctable errors have been encountered during the verify
operation
Erase P-Flash Sector Command
The Erase P-Flash Sector operation will erase all addresses in a P-Flash sector.
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Table 13-47. Erase P-Flash Sector Command FCCOB Requirements
CCOBIX[2:0]
000
001
FCCOB Parameters
0x0A
Global address [17:16] to identify
P-Flash block to be erased
Global address [15:0] anywhere within the sector to be erased.
Refer to Section 13.1.2.1 for the P-Flash sector size.
Upon clearing CCIF to launch the Erase P-Flash Sector command, the Memory Controller will erase the
selected Flash sector and then verify that it is erased. The CCIF flag will be set after the Erase P-Flash
Sector operation has completed.
Table 13-48. Erase P-Flash Sector Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 001 at command launch
Set if command not available in current mode (see Table 13-27)
ACCERR
Set if an invalid global address [17:16] is supplied
Set if a misaligned phrase address is supplied (global address [2:0] != 000)
FSTAT
FPVIOL
Set if the selected P-Flash sector is protected
MGSTAT1
Set if any errors have been encountered during the verify operation
MGSTAT0
Set if any non-correctable errors have been encountered during the verify
operation
13.4.5.10 Unsecure Flash Command
The Unsecure Flash command will erase the entire P-Flash and D-Flash memory space and, if the erase is
successful, will release security.
Table 13-49. Unsecure Flash Command FCCOB Requirements
CCOBIX[2:0]
000
FCCOB Parameters
0x0B
Not required
Upon clearing CCIF to launch the Unsecure Flash command, the Memory Controller will erase the entire
P-Flash and D-Flash memory space and verify that it is erased. If the Memory Controller verifies that the
entire Flash memory space was properly erased, security will be released. If the erase verify is not
successful, the Unsecure Flash operation sets MGSTAT1 and terminates without changing the security
state. During the execution of this command (CCIF=0) the user must not write to any Flash module
register. The CCIF flag is set after the Unsecure Flash operation has completed.
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Table 13-50. Unsecure Flash Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 000 at command launch
ACCERR
Set if command not available in current mode (see Table 13-27)
FPVIOL
FSTAT
Set if any area of the P-Flash or D-Flash memory is protected
MGSTAT1
Set if any errors have been encountered during the verify operation
MGSTAT0
Set if any non-correctable errors have been encountered during the verify
operation
13.4.5.11 Verify Backdoor Access Key Command
The Verify Backdoor Access Key command will only execute if it is enabled by the KEYEN bits in the
FSEC register (see Table 13-9). The Verify Backdoor Access Key command releases security if usersupplied keys match those stored in the Flash security bytes of the Flash configuration field (see Table 133). The Verify Backdoor Access Key command must not be executed from the Flash block containing the
backdoor comparison key to avoid code runaway.
Table 13-51. Verify Backdoor Access Key Command FCCOB Requirements
CCOBIX[2:0]
000
FCCOB Parameters
0x0C
Not required
001
Key 0
010
Key 1
011
Key 2
100
Key 3
Upon clearing CCIF to launch the Verify Backdoor Access Key command, the Memory Controller will
check the FSEC KEYEN bits to verify that this command is enabled. If not enabled, the Memory
Controller sets the ACCERR bit in the FSTAT register and terminates. If the command is enabled, the
Memory Controller compares the key provided in FCCOB to the backdoor comparison key in the Flash
configuration field with Key 0 compared to 0x3_FF00, etc. If the backdoor keys match, security will be
released. If the backdoor keys do not match, security is not released and all future attempts to execute the
Verify Backdoor Access Key command are aborted (set ACCERR) until a reset occurs. The CCIF flag is
set after the Verify Backdoor Access Key operation has completed.
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Table 13-52. Verify Backdoor Access Key Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 100 at command launch
Set if an incorrect backdoor key is supplied
ACCERR
FSTAT
Set if backdoor key access has not been enabled (KEYEN[1:0] != 10, see
Section 13.3.2.2)
Set if the backdoor key has mismatched since the last reset
FPVIOL
None
MGSTAT1
None
MGSTAT0
None
13.4.5.12 Set User Margin Level Command
The Set User Margin Level command causes the Memory Controller to set the margin level for future read
operations of the P-Flash or D-Flash block.
Table 13-53. Set User Margin Level Command FCCOB Requirements
CCOBIX[2:0]
FCCOB Parameters
000
0x0D
001
Global address [17:16] to identify the
Flash block
Margin level setting
Upon clearing CCIF to launch the Set User Margin Level command, the Memory Controller will set the
user margin level for the targeted block and then set the CCIF flag.
NOTE
When the D-Flash block is targeted, the D-Flash user margin levels are
applied only to the D-Flash reads. However, when the P-Flash block is
targeted, the P-Flash user margin levels are applied to both P-Flash and DFlash reads. It is not possible to apply user margin levels to the P-Flash
block only.
Valid margin level settings for the Set User Margin Level command are defined in Table 13-54.
Table 13-54. Valid Set User Margin Level Settings
CCOB
(CCOBIX=001)
Level Description
0x0000
Return to Normal Level
0x0001
User Margin-1 Level(1)
0x0002
User Margin-0 Level(2)
1. Read margin to the erased state
2. Read margin to the programmed state
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Table 13-55. Set User Margin Level Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 001 at command launch
Set if command not available in current mode (see Table 13-27)
ACCERR
Set if an invalid global address [17:16] is supplied
FSTAT
Set if an invalid margin level setting is supplied
FPVIOL
None
MGSTAT1
None
MGSTAT0
None
NOTE
User margin levels can be used to check that Flash memory contents have
adequate margin for normal level read operations. If unexpected results are
encountered when checking Flash memory contents at user margin levels, a
potential loss of information has been detected.
13.4.5.13 Set Field Margin Level Command
The Set Field Margin Level command, valid in special modes only, causes the Memory Controller to set
the margin level specified for future read operations of the P-Flash or D-Flash block.
Table 13-56. Set Field Margin Level Command FCCOB Requirements
CCOBIX[2:0]
000
001
FCCOB Parameters
0x0E
Global address [17:16] to identify the Flash
block
Margin level setting
Upon clearing CCIF to launch the Set Field Margin Level command, the Memory Controller will set the
field margin level for the targeted block and then set the CCIF flag.
NOTE
When the D-Flash block is targeted, the D-Flash field margin levels are
applied only to the D-Flash reads. However, when the P-Flash block is
targeted, the P-Flash field margin levels are applied to both P-Flash and DFlash reads. It is not possible to apply field margin levels to the P-Flash
block only.
Valid margin level settings for the Set Field Margin Level command are defined in Table 13-57.
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Table 13-57. Valid Set Field Margin Level Settings
CCOB
(CCOBIX=001)
Level Description
0x0000
Return to Normal Level
0x0001
User Margin-1 Level(1)
0x0002
User Margin-0 Level(2)
0x0003
Field Margin-1 Level1
0x0004
Field Margin-0 Level2
1. Read margin to the erased state
2. Read margin to the programmed state
Table 13-58. Set Field Margin Level Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 001 at command launch
Set if command not available in current mode (see Table 13-27)
ACCERR
Set if an invalid global address [17:16] is supplied
FSTAT
Set if an invalid margin level setting is supplied
FPVIOL
None
MGSTAT1
None
MGSTAT0
None
CAUTION
Field margin levels must only be used during verify of the initial factory
programming.
NOTE
Field margin levels can be used to check that Flash memory contents have
adequate margin for data retention at the normal level setting. If unexpected
results are encountered when checking Flash memory contents at field
margin levels, the Flash memory contents should be erased and
reprogrammed.
13.4.5.14 Erase Verify D-Flash Section Command
The Erase Verify D-Flash Section command will verify that a section of code in the D-Flash is erased. The
Erase Verify D-Flash Section command defines the starting point of the data to be verified and the number
of words.
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Table 13-59. Erase Verify D-Flash Section Command FCCOB Requirements
CCOBIX[2:0]
FCCOB Parameters
000
0x10
Global address [17:16] to
identify the D-Flash block
001
Global address [15:0] of the first word to be verified
010
Number of words to be verified
Upon clearing CCIF to launch the Erase Verify D-Flash Section command, the Memory Controller will
verify the selected section of D-Flash memory is erased. The CCIF flag will set after the Erase Verify DFlash Section operation has completed.
Table 13-60. Erase Verify D-Flash Section Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 010 at command launch
Set if command not available in current mode (see Table 13-27)
ACCERR
Set if an invalid global address [17:0] is supplied
Set if a misaligned word address is supplied (global address [0] != 0)
FSTAT
Set if the requested section breaches the end of the D-Flash block
FPVIOL
None
MGSTAT1
Set if any errors have been encountered during the read
MGSTAT0
Set if any non-correctable errors have been encountered during the read
13.4.5.15 Program D-Flash Command
The Program D-Flash operation programs one to four previously erased words in the D-Flash block. The
Program D-Flash operation will confirm that the targeted location(s) were successfully programmed upon
completion.
CAUTION
A Flash word must be in the erased state before being programmed.
Cumulative programming of bits within a Flash word is not allowed.
Table 13-61. Program D-Flash Command FCCOB Requirements
CCOBIX[2:0]
000
FCCOB Parameters
0x11
Global address [17:16] to
identify the D-Flash block
001
Global address [15:0] of word to be programmed
010
Word 0 program value
011
Word 1 program value, if desired
100
Word 2 program value, if desired
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128 KByte Flash Module (S12FTMRC128K1V1)
Table 13-61. Program D-Flash Command FCCOB Requirements
CCOBIX[2:0]
FCCOB Parameters
101
Word 3 program value, if desired
Upon clearing CCIF to launch the Program D-Flash command, the user-supplied words will be transferred
to the Memory Controller and be programmed if the area is unprotected. The CCOBIX index value at
Program D-Flash command launch determines how many words will be programmed in the D-Flash block.
The CCIF flag is set when the operation has completed.
Table 13-62. Program D-Flash Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] < 010 at command launch
Set if CCOBIX[2:0] > 101 at command launch
Set if command not available in current mode (see Table 13-27)
ACCERR
Set if an invalid global address [17:0] is supplied
Set if a misaligned word address is supplied (global address [0] != 0)
FSTAT
Set if the requested group of words breaches the end of the D-Flash block
FPVIOL
Set if the selected area of the D-Flash memory is protected
MGSTAT1
Set if any errors have been encountered during the verify operation
MGSTAT0
Set if any non-correctable errors have been encountered during the verify
operation
13.4.5.16 Erase D-Flash Sector Command
The Erase D-Flash Sector operation will erase all addresses in a sector of the D-Flash block.
Table 13-63. Erase D-Flash Sector Command FCCOB Requirements
CCOBIX[2:0]
000
001
FCCOB Parameters
0x12
Global address [17:16] to identify
D-Flash block
Global address [15:0] anywhere within the sector to be erased.
See Section 13.1.2.2 for D-Flash sector size.
Upon clearing CCIF to launch the Erase D-Flash Sector command, the Memory Controller will erase the
selected Flash sector and verify that it is erased. The CCIF flag will set after the Erase D-Flash Sector
operation has completed.
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Table 13-64. Erase D-Flash Sector Command Error Handling
Register
Error Bit
Error Condition
Set if CCOBIX[2:0] != 001 at command launch
Set if command not available in current mode (see Table 13-27)
ACCERR
Set if an invalid global address [17:0] is supplied
Set if a misaligned word address is supplied (global address [0] != 0)
FSTAT
FPVIOL
13.4.6
Set if the selected area of the D-Flash memory is protected
MGSTAT1
Set if any errors have been encountered during the verify operation
MGSTAT0
Set if any non-correctable errors have been encountered during the verify
operation
Interrupts
The Flash module can generate an interrupt when a Flash command operation has completed or when a
Flash command operation has detected an ECC fault.
Table 13-65. Flash Interrupt Sources
Interrupt Source
Global (CCR)
Mask
Interrupt Flag
Local Enable
CCIF
(FSTAT register)
CCIE
(FCNFG register)
I Bit
ECC Double Bit Fault on Flash Read
DFDIF
(FERSTAT register)
DFDIE
(FERCNFG register)
I Bit
ECC Single Bit Fault on Flash Read
SFDIF
(FERSTAT register)
SFDIE
(FERCNFG register)
I Bit
Flash Command Complete
NOTE
Vector addresses and their relative interrupt priority are determined at the
MCU level.
13.4.6.1
Description of Flash Interrupt Operation
The Flash module uses the CCIF flag in combination with the CCIE interrupt enable bit to generate the
Flash command interrupt request. The Flash module uses the DFDIF and SFDIF flags in combination with
the DFDIE and SFDIE interrupt enable bits to generate the Flash error interrupt request. For a detailed
description of the register bits involved, refer to Section 13.3.2.5, “Flash Configuration Register
(FCNFG)”, Section 13.3.2.6, “Flash Error Configuration Register (FERCNFG)”, Section 13.3.2.7, “Flash
Status Register (FSTAT)”, and Section 13.3.2.8, “Flash Error Status Register (FERSTAT)”.
The logic used for generating the Flash module interrupts is shown in Figure 13-27.
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128 KByte Flash Module (S12FTMRC128K1V1)
Flash Command Interrupt Request
CCIE
CCIF
DFDIE
DFDIF
Flash Error Interrupt Request
SFDIE
SFDIF
Figure 13-27. Flash Module Interrupts Implementation
13.4.7
Wait Mode
The Flash module is not affected if the MCU enters wait mode. The Flash module can recover the MCU
from wait via the CCIF interrupt (see Section 13.4.6, “Interrupts”).
13.4.8
Stop Mode
If a Flash command is active (CCIF = 0) when the MCU requests stop mode, the current Flash operation
will be completed before the CPU is allowed to enter stop mode.
13.5
Security
The Flash module provides security information to the MCU. The Flash security state is defined by the
SEC bits of the FSEC register (see Table 13-10). During reset, the Flash module initializes the FSEC
register using data read from the security byte of the Flash configuration field at global address 0x3_FF0F.
The security state out of reset can be permanently changed by programming the security byte assuming
that the MCU is starting from a mode where the necessary P-Flash erase and program commands are
available and that the upper region of the P-Flash is unprotected. If the Flash security byte is successfully
programmed, its new value will take affect after the next MCU reset.
The following subsections describe these security-related subjects:
• Unsecuring the MCU using Backdoor Key Access
• Unsecuring the MCU in Special Single Chip Mode using BDM
• Mode and Security Effects on Flash Command Availability
13.5.1
Unsecuring the MCU using Backdoor Key Access
The MCU may be unsecured by using the backdoor key access feature which requires knowledge of the
contents of the backdoor keys (four 16-bit words programmed at addresses 0x3_FF00-0x3_FF07). If the
KEYEN[1:0] bits are in the enabled state (see Section 13.3.2.2), the Verify Backdoor Access Key
command (see Section 13.4.5.11) allows the user to present four prospective keys for comparison to the
keys stored in the Flash memory via the Memory Controller. If the keys presented in the Verify Backdoor
Access Key command match the backdoor keys stored in the Flash memory, the SEC bits in the FSEC
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128 KByte Flash Module (S12FTMRC128K1V1)
register (see Table 13-10) will be changed to unsecure the MCU. Key values of 0x0000 and 0xFFFF are
not permitted as backdoor keys. While the Verify Backdoor Access Key command is active, P-Flash
memory and D-Flash memory will not be available for read access and will return invalid data.
The user code stored in the P-Flash memory must have a method of receiving the backdoor keys from an
external stimulus. This external stimulus would typically be through one of the on-chip serial ports.
If the KEYEN[1:0] bits are in the enabled state (see Section 13.3.2.2), the MCU can be unsecured by the
backdoor key access sequence described below:
1. Follow the command sequence for the Verify Backdoor Access Key command as explained in
Section 13.4.5.11
2. If the Verify Backdoor Access Key command is successful, the MCU is unsecured and the
SEC[1:0] bits in the FSEC register are forced to the unsecure state of 10
The Verify Backdoor Access Key command is monitored by the Memory Controller and an illegal key will
prohibit future use of the Verify Backdoor Access Key command. A reset of the MCU is the only method
to re-enable the Verify Backdoor Access Key command. The security as defined in the Flash security byte
(0x3_FF0F) is not changed by using the Verify Backdoor Access Key command sequence. The backdoor
keys stored in addresses 0x3_FF00-0x3_FF07 are unaffected by the Verify Backdoor Access Key
command sequence. The Verify Backdoor Access Key command sequence has no effect on the program
and erase protections defined in the Flash protection register, FPROT.
After the backdoor keys have been correctly matched, the MCU will be unsecured. After the MCU is
unsecured, the sector containing the Flash security byte can be erased and the Flash security byte can be
reprogrammed to the unsecure state, if desired. In the unsecure state, the user has full control of the
contents of the backdoor keys by programming addresses 0x3_FF00-0x3_FF07 in the Flash configuration
field.
13.5.2
Unsecuring the MCU in Special Single Chip Mode using BDM
A secured MCU can be unsecured in special single chip mode by using the following method to erase the
P-Flash and D-Flash memory:
1. Reset the MCU into special single chip mode
2. Delay while the BDM executes the Erase Verify All Blocks command write sequence to check if
the P-Flash and D-Flash memories are erased
3. Send BDM commands to disable protection in the P-Flash and D-Flash memory
4. Execute the Erase All Blocks command write sequence to erase the P-Flash and D-Flash memory
5. After the CCIF flag sets to indicate that the Erase All Blocks operation has completed, reset the
MCU into special single chip mode
6. Delay while the BDM executes the Erase Verify All Blocks command write sequence to verify that
the P-Flash and D-Flash memory are erased
If the P-Flash and D-Flash memory are verified as erased, the MCU will be unsecured. All BDM
commands will now be enabled and the Flash security byte may be programmed to the unsecure state by
continuing with the following steps:
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128 KByte Flash Module (S12FTMRC128K1V1)
7. Send BDM commands to execute the Program P-Flash command write sequence to program the
Flash security byte to the unsecured state
8. Reset the MCU
13.5.3
Mode and Security Effects on Flash Command Availability
The availability of Flash module commands depends on the MCU operating mode and security state as
shown in Table 13-27.
13.6
Initialization
On each system reset the Flash module executes a reset sequence which establishes initial values for the
Flash Block Configuration Parameters, the FPROT and DFPROT protection registers, and the FOPT and
FSEC registers. The Flash module reverts to using built-in default values that leave the module in a fully
protected and secured state if errors are encountered during execution of the reset sequence. If a double bit
fault is detected during the reset sequence, both MGSTAT bits in the FSTAT register will be set.
CCIF remains clear throughout the reset sequence. The Flash module holds off all CPU access for the
initial portion of the reset sequence. While Flash memory reads and access to most Flash registers are
possible when the hold is removed, writes to the FCCOBIX, FCCOBHI, and FCCOBLO registers are
ignored. Completion of the reset sequence is marked by setting CCIF high which enables writes to the
FCCOBIX, FCCOBHI, and FCCOBLO registers to launch any available Flash command.
If a reset occurs while any Flash command is in progress, that command will be immediately aborted. The
state of the word being programmed or the sector/block being erased is not guaranteed.
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Chapter 14
Timer Module (TIM16B8CV2) Block Description
Table 14-1. Revision History
Revision
Number
Revision Date
V02.04
1 Jul 2008
14.3.2.12/14488
14.3.2.13/14489
14.3.2.16/14492
14.4.2/14-497
14.4.3/14-497
- Revised flag clearing procedure, whereby TEN bit must be set when clearing
flags.
V02.05
9 Jul 2009
14.3.2.12/14488
14.3.2.13/14489
14.3.2.15/14491
14.3.2.16/14492
14.3.2.19/14494
14.4.2/14-497
14.4.3/14-497
- Revised flag clearing procedure, whereby TEN or PAEN bit must be set
when clearing flags.
- Add fomula to describe prescaler
V02.06
26 Aug 2009
14.1.2/14-474
14.3.2.15/14491
14.3.2.2/14-480
14.3.2.3/14-481
14.3.2.4/14-482
14.4.3/14-497
14.1
Sections
Affected
Description of Changes
- Correct typo: TSCR ->TSCR1
- Correct reference: Figure 1-25 -> Figure 1-31
- Add description, “a counter overflow when TTOV[7] is set”, to be the
condition of channel 7 override event.
- Phrase the description of OC7M to make it more explicit
Introduction
The basic timer consists of a 16-bit, software-programmable counter driven by a enhanced programmable
prescaler.
This timer can be used for many purposes, including input waveform measurements while simultaneously
generating an output waveform. Pulse widths can vary from microseconds to many seconds.
This timer contains 8 complete input capture/output compare channels and one pulse accumulator. The
input capture function is used to detect a selected transition edge and record the time. The output compare
function is used for generating output signals or for timer software delays. The 16-bit pulse accumulator
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Timer Module (TIM16B8CV2) Block Description
is used to operate as a simple event counter or a gated time accumulator. The pulse accumulator shares
timer channel 7 when in event mode.
A full access for the counter registers or the input capture/output compare registers should take place in
one clock cycle. Accessing high byte and low byte separately for all of these registers may not yield the
same result as accessing them in one word.
14.1.1
Features
The TIM16B8CV2 includes these distinctive features:
• Eight input capture/output compare channels.
• Clock prescaling.
• 16-bit counter.
• 16-bit pulse accumulator.
14.1.2
Modes of Operation
Stop:
Timer is off because clocks are stopped.
Freeze:
Timer counter keep on running, unless TSFRZ in TSCR1 (0x0006) is set to 1.
Wait:
Counters keep on running, unless TSWAI in TSCR1 (0x0006) is set to 1.
Normal:
Timer counter keep on running, unless TEN in TSCR1 (0x0006) is cleared to 0.
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Timer Module (TIM16B8CV2) Block Description
14.1.3
Block Diagrams
Bus clock
Prescaler
16-bit Counter
Channel 0
Input capture
Output compare
Channel 1
Input capture
Output compare
Channel 2
Input capture
Output compare
Timer overflow
interrupt
Timer channel 0
interrupt
Channel 3
Input capture
Output compare
Registers
Channel 4
Input capture
Output compare
Channel 5
Input capture
Output compare
Timer channel 7
interrupt
PA overflow
interrupt
PA input
interrupt
Channel 6
Input capture
Output compare
16-bit
Pulse accumulator
Channel 7
Input capture
Output compare
IOC0
IOC1
IOC2
IOC3
IOC4
IOC5
IOC6
IOC7
Figure 14-1. TIM16B8CV2 Block Diagram
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Timer Module (TIM16B8CV2) Block Description
TIMCLK (Timer clock)
CLK1
CLK0
Intermodule Bus
Clock select
(PAMOD)
Edge detector
PT7
PACLK
PACLK / 256
PACLK / 65536
Prescaled clock
(PCLK)
4:1 MUX
Interrupt
PACNT
MUX
Divide by 64
M clock
Figure 14-2. 16-Bit Pulse Accumulator Block Diagram
16-bit Main Timer
PTn
Edge detector
Set CnF Interrupt
TCn Input Capture Reg.
Figure 14-3. Interrupt Flag Setting
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Timer Module (TIM16B8CV2) Block Description
PULSE
ACCUMULATOR
PAD
CHANNEL 7 OUTPUT COMPARE
OCPD
TEN
TIOS7
Figure 14-4. Channel 7 Output Compare/Pulse Accumulator Logic
14.2
External Signal Description
The TIM16B8CV2 module has a total of eight external pins.
14.2.1
IOC7 — Input Capture and Output Compare Channel 7 Pin
This pin serves as input capture or output compare for channel 7. This can also be configured as pulse
accumulator input.
14.2.2
IOC6 — Input Capture and Output Compare Channel 6 Pin
This pin serves as input capture or output compare for channel 6.
14.2.3
IOC5 — Input Capture and Output Compare Channel 5 Pin
This pin serves as input capture or output compare for channel 5.
14.2.4
IOC4 — Input Capture and Output Compare Channel 4 Pin
This pin serves as input capture or output compare for channel 4. Pin
14.2.5
IOC3 — Input Capture and Output Compare Channel 3 Pin
This pin serves as input capture or output compare for channel 3.
14.2.6
IOC2 — Input Capture and Output Compare Channel 2 Pin
This pin serves as input capture or output compare for channel 2.
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Timer Module (TIM16B8CV2) Block Description
14.2.7
IOC1 — Input Capture and Output Compare Channel 1 Pin
This pin serves as input capture or output compare for channel 1.
14.2.8
IOC0 — Input Capture and Output Compare Channel 0 Pin
This pin serves as input capture or output compare for channel 0.
NOTE
For the description of interrupts see Section 14.6, “Interrupts”.
14.3
Memory Map and Register Definition
This section provides a detailed description of all memory and registers.
14.3.1
Module Memory Map
The memory map for the TIM16B8CV2 module is given below in Figure 14-5. The address listed for each
register is the address offset. The total address for each register is the sum of the base address for the
TIM16B8CV2 module and the address offset for each register.
14.3.2
Register Descriptions
This section consists of register descriptions in address order. Each description includes a standard
register diagram with an associated figure number. Details of register bit and field function follow the
register diagrams, in bit order.
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
0x0000
TIOS
R
W
IOS7
IOS6
IOS5
IOS4
IOS3
IOS2
IOS1
IOS0
0x0001
CFORC
R
W
0
FOC7
0
FOC6
0
FOC5
0
FOC4
0
FOC3
0
FOC2
0
FOC1
0
FOC0
0x0002
OC7M
R
W
OC7M7
OC7M6
OC7M5
OC7M4
OC7M3
OC7M2
OC7M1
OC7M0
0x0003
OC7D
R
W
OC7D7
OC7D6
OC7D5
OC7D4
OC7D3
OC7D2
OC7D1
OC7D0
0x0004
TCNTH
R
W
TCNT15
TCNT14
TCNT13
TCNT12
TCNT11
TCNT10
TCNT9
TCNT8
0x0005
TCNTL
R
W
TCNT7
TCNT6
TCNT5
TCNT4
TCNT3
TCNT2
TCNT1
TCNT0
= Unimplemented or Reserved
Figure 14-5. TIM16B8CV2 Register Summary (Sheet 1 of 3)
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Timer Module (TIM16B8CV2) Block Description
Register
Name
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0x0006
TSCR1
R
W
TEN
TSWAI
TSFRZ
TFFCA
PRNT
0x0007
TTOV
R
W
TOV7
TOV6
TOV5
TOV4
TOV3
TOV2
TOV1
TOV0
0x0008
TCTL1
R
W
OM7
OL7
OM6
OL6
OM5
OL5
OM4
OL4
0x0009
TCTL2
R
W
OM3
OL3
OM2
OL2
OM1
OL1
OM0
OL0
0x000A
TCTL3
R
W
EDG7B
EDG7A
EDG6B
EDG6A
EDG5B
EDG5A
EDG4B
EDG4A
0x000B
TCTL4
R
W
EDG3B
EDG3A
EDG2B
EDG2A
EDG1B
EDG1A
EDG0B
EDG0A
0x000C
TIE
R
W
C7I
C6I
C5I
C4I
C3I
C2I
C1I
C0I
0x000D
TSCR2
R
W
TOI
0
0
0
TCRE
PR2
PR1
PR0
0x000E
TFLG1
R
W
C7F
C6F
C5F
C4F
C3F
C2F
C1F
C0F
0x000F
TFLG2
R
W
TOF
0
0
0
0
0
0
0
R
W
Bit 15
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PAEN
PAMOD
PEDGE
CLK1
CLK0
PAOVI
PAI
0
0
0
0
0
PAOVF
PAIF
0x0010–0x001F
TCxH–TCxL
0x0020
PACTL
R
W
0
0x0021
PAFLG
R
W
0
0x0022
PACNTH
R
PACNT15
W
PACNT14
PACNT13
PACNT12
PACNT11
PACNT10
PACNT9
PACNT8
0x0023
PACNTL
R
W
PACNT6
PACNT5
PACNT4
PACNT3
PACNT2
PACNT1
PACNT0
0x0024–0x002B
Reserved
R
W
PACNT7
= Unimplemented or Reserved
Figure 14-5. TIM16B8CV2 Register Summary (Sheet 2 of 3)
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Timer Module (TIM16B8CV2) Block Description
Register
Name
0x002C
OCPD
R
W
0x002D
R
0x002E
PTPSR
R
W
0x002F
Reserved
R
W
Bit 7
6
5
4
3
2
1
Bit 0
OCPD7
OCPD6
OCPD5
OCPD4
OCPD3
OCPD2
OCPD1
OCPD0
PTPS7
PTPS6
PTPS5
PTPS4
PTPS3
PTPS2
PTPS1
PTPS0
= Unimplemented or Reserved
Figure 14-5. TIM16B8CV2 Register Summary (Sheet 3 of 3)
14.3.2.1
Timer Input Capture/Output Compare Select (TIOS)
Module Base + 0x0000
7
6
5
4
3
2
1
0
IOS7
IOS6
IOS5
IOS4
IOS3
IOS2
IOS1
IOS0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-6. Timer Input Capture/Output Compare Select (TIOS)
Read: Anytime
Write: Anytime
Table 14-2. TIOS Field Descriptions
Field
7:0
IOS[7:0]
14.3.2.2
Description
Input Capture or Output Compare Channel Configuration
0 The corresponding channel acts as an input capture.
1 The corresponding channel acts as an output compare.
Timer Compare Force Register (CFORC)
Module Base + 0x0001
7
6
5
4
3
2
1
0
R
0
0
0
0
0
0
0
0
W
FOC7
FOC6
FOC5
FOC4
FOC3
FOC2
FOC1
FOC0
0
0
0
0
0
0
0
0
Reset
Figure 14-7. Timer Compare Force Register (CFORC)
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Timer Module (TIM16B8CV2) Block Description
Read: Anytime but will always return 0x0000 (1 state is transient)
Write: Anytime
Table 14-3. CFORC Field Descriptions
Field
Description
7:0
FOC[7:0]
Force Output Compare Action for Channel 7:0 — A write to this register with the corresponding data bit(s) set
causes the action which is programmed for output compare “x” to occur immediately. The action taken is the
same as if a successful comparison had just taken place with the TCx register except the interrupt flag does not
get set.
Note: A channel 7 event, which can be a counter overflow when TTOV[7] is set or a successful output compare
on channel 7, overrides any channel 6:0 compares. If forced output compare on any channel occurs at the
same time as the successful output compare then forced output compare action will take precedence and
interrupt flag won’t get set.
14.3.2.3
Output Compare 7 Mask Register (OC7M)
Module Base + 0x0002
7
6
5
4
3
2
1
0
OC7M7
OC7M6
OC7M5
OC7M4
OC7M3
OC7M2
OC7M1
OC7M0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-8. Output Compare 7 Mask Register (OC7M)
Read: Anytime
Write: Anytime
Table 14-4. OC7M Field Descriptions
Field
Description
7:0
OC7M[7:0]
Output Compare 7 Mask — A channel 7 event, which can be a counter overflow when TTOV[7] is set or a
successful output compare on channel 7, overrides any channel 6:0 compares. For each OC7M bit that is set,
the output compare action reflects the corresponding OC7D bit.
0 The corresponding OC7Dx bit in the output compare 7 data register will not be transferred to the timer port on
a channel 7 event, even if the corresponding pin is setup for output compare.
1 The corresponding OC7Dx bit in the output compare 7 data register will be transferred to the timer port on a
channel 7 event.
Note: The corresponding channel must also be setup for output compare (IOSx = 1 and OCPDx = 0) for data to
be transferred from the output compare 7 data register to the timer port.
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Timer Module (TIM16B8CV2) Block Description
14.3.2.4
Output Compare 7 Data Register (OC7D)
Module Base + 0x0003
7
6
5
4
3
2
1
0
OC7D7
OC7D6
OC7D5
OC7D4
OC7D3
OC7D2
OC7D1
OC7D0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-9. Output Compare 7 Data Register (OC7D)
Read: Anytime
Write: Anytime
Table 14-5. OC7D Field Descriptions
Field
Description
7:0
OC7D[7:0]
Output Compare 7 Data — A channel 7 event, which can be a counter overflow when TTOV[7] is set or a
successful output compare on channel 7, can cause bits in the output compare 7 data register to transfer to the
timer port data register depending on the output compare 7 mask register.
14.3.2.5
Timer Count Register (TCNT)
Module Base + 0x0004
15
14
13
12
11
10
9
9
TCNT15
TCNT14
TCNT13
TCNT12
TCNT11
TCNT10
TCNT9
TCNT8
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-10. Timer Count Register High (TCNTH)
Module Base + 0x0005
7
6
5
4
3
2
1
0
TCNT7
TCNT6
TCNT5
TCNT4
TCNT3
TCNT2
TCNT1
TCNT0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-11. Timer Count Register Low (TCNTL)
The 16-bit main timer is an up counter.
A full access for the counter register should take place in one clock cycle. A separate read/write for high
byte and low byte will give a different result than accessing them as a word.
Read: Anytime
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Timer Module (TIM16B8CV2) Block Description
Write: Has no meaning or effect in the normal mode; only writable in special modes (test_mode = 1).
The period of the first count after a write to the TCNT registers may be a different size because the write
is not synchronized with the prescaler clock.
14.3.2.6
Timer System Control Register 1 (TSCR1)
Module Base + 0x0006
7
6
5
4
3
TEN
TSWAI
TSFRZ
TFFCA
PRNT
0
0
0
0
0
R
2
1
0
0
0
0
0
0
0
W
Reset
= Unimplemented or Reserved
Figure 14-12. Timer System Control Register 1 (TSCR1)
Read: Anytime
Write: Anytime
Table 14-6. TSCR1 Field Descriptions
Field
7
TEN
Description
Timer Enable
0 Disables the main timer, including the counter. Can be used for reducing power consumption.
1 Allows the timer to function normally.
If for any reason the timer is not active, there is no ÷64 clock for the pulse accumulator because the ÷64 is
generated by the timer prescaler.
6
TSWAI
Timer Module Stops While in Wait
0 Allows the timer module to continue running during wait.
1 Disables the timer module when the MCU is in the wait mode. Timer interrupts cannot be used to get the MCU
out of wait.
TSWAI also affects pulse accumulator.
5
TSFRZ
Timer Stops While in Freeze Mode
0 Allows the timer counter to continue running while in freeze mode.
1 Disables the timer counter whenever the MCU is in freeze mode. This is useful for emulation.
TSFRZ does not stop the pulse accumulator.
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Timer Module (TIM16B8CV2) Block Description
Table 14-6. TSCR1 Field Descriptions (continued)
Field
Description
4
TFFCA
Timer Fast Flag Clear All
0 Allows the timer flag clearing to function normally.
1 For TFLG1(0x000E), a read from an input capture or a write to the output compare channel (0x0010–0x001F)
causes the corresponding channel flag, CnF, to be cleared. For TFLG2 (0x000F), any access to the TCNT
register (0x0004, 0x0005) clears the TOF flag. Any access to the PACNT registers (0x0022, 0x0023) clears
the PAOVF and PAIF flags in the PAFLG register (0x0021). This has the advantage of eliminating software
overhead in a separate clear sequence. Extra care is required to avoid accidental flag clearing due to
unintended accesses.
3
PRNT
Precision Timer
0 Enables legacy timer. PR0, PR1, and PR2 bits of the TSCR2 register are used for timer counter prescaler
selection.
1 Enables precision timer. All bits of the PTPSR register are used for Precision Timer Prescaler Selection, and
all bits.
This bit is writable only once out of reset.
14.3.2.7
Timer Toggle On Overflow Register 1 (TTOV)
Module Base + 0x0007
7
6
5
4
3
2
1
0
TOV7
TOV6
TOV5
TOV4
TOV3
TOV2
TOV1
TOV0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-13. Timer Toggle On Overflow Register 1 (TTOV)
Read: Anytime
Write: Anytime
Table 14-7. TTOV Field Descriptions
Field
Description
7:0
TOV[7:0]
Toggle On Overflow Bits — TOVx toggles output compare pin on overflow. This feature only takes effect when
in output compare mode. When set, it takes precedence over forced output compare but not channel 7 override
events.
0 Toggle output compare pin on overflow feature disabled.
1 Toggle output compare pin on overflow feature enabled.
S12P-Family Reference Manual, Rev. 1.13
484
Freescale Semiconductor
Timer Module (TIM16B8CV2) Block Description
14.3.2.8
Timer Control Register 1/Timer Control Register 2 (TCTL1/TCTL2)
Module Base + 0x0008
7
6
5
4
3
2
1
0
OM7
OL7
OM6
OL6
OM5
OL5
OM4
OL4
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-14. Timer Control Register 1 (TCTL1)
Module Base + 0x0009
7
6
5
4
3
2
1
0
OM3
OL3
OM2
OL2
OM1
OL1
OM0
OL0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-15. Timer Control Register 2 (TCTL2)
Read: Anytime
Write: Anytime
Table 14-8. TCTL1/TCTL2 Field Descriptions
Field
Description
7:0
OMx
Output Mode — These eight pairs of control bits are encoded to specify the output action to be taken as a result
of a successful OCx compare. When either OMx or OLx is 1, the pin associated with OCx becomes an output
tied to OCx.
Note: To enable output action by OMx bits on timer port, the corresponding bit in OC7M should be cleared. For
an output line to be driven by an OCx the OCPDx must be cleared.
7:0
OLx
Output Level — These eight pairs of control bits are encoded to specify the output action to be taken as a result
of a successful OCx compare. When either OMx or OLx is 1, the pin associated with OCx becomes an output
tied to OCx.
Note: To enable output action by OLx bits on timer port, the corresponding bit in OC7M should be cleared. For
an output line to be driven by an OCx the OCPDx must be cleared.
Table 14-9. Compare Result Output Action
OMx
OLx
Action
0
0
No output compare
action on the timer output signal
0
1
Toggle OCx output line
1
0
Clear OCx output line to zero
1
1
Set OCx output line to one
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
485
Timer Module (TIM16B8CV2) Block Description
To operate the 16-bit pulse accumulator independently of input capture or output compare 7 and 0
respectively the user must set the corresponding bits IOSx = 1, OMx = 0 and OLx = 0. OC7M7 in the
OC7M register must also be cleared.
14.3.2.9
Timer Control Register 3/Timer Control Register 4 (TCTL3 and TCTL4)
Module Base + 0x000A
7
6
5
4
3
2
1
0
EDG7B
EDG7A
EDG6B
EDG6A
EDG5B
EDG5A
EDG4B
EDG4A
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-16. Timer Control Register 3 (TCTL3)
Module Base + 0x000B
7
6
5
4
3
2
1
0
EDG3B
EDG3A
EDG2B
EDG2A
EDG1B
EDG1A
EDG0B
EDG0A
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-17. Timer Control Register 4 (TCTL4)
Read: Anytime
Write: Anytime.
Table 14-10. TCTL3/TCTL4 Field Descriptions
Field
7:0
EDGnB
EDGnA
Description
Input Capture Edge Control — These eight pairs of control bits configure the input capture edge detector
circuits.
Table 14-11. Edge Detector Circuit Configuration
EDGnB
EDGnA
Configuration
0
0
Capture disabled
0
1
Capture on rising edges only
1
0
Capture on falling edges only
1
1
Capture on any edge (rising or falling)
S12P-Family Reference Manual, Rev. 1.13
486
Freescale Semiconductor
Timer Module (TIM16B8CV2) Block Description
14.3.2.10 Timer Interrupt Enable Register (TIE)
Module Base + 0x000C
7
6
5
4
3
2
1
0
C7I
C6I
C5I
C4I
C3I
C2I
C1I
C0I
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-18. Timer Interrupt Enable Register (TIE)
Read: Anytime
Write: Anytime.
Table 14-12. TIE Field Descriptions
Field
Description
7:0
C7I:C0I
Input Capture/Output Compare “x” Interrupt Enable — The bits in TIE correspond bit-for-bit with the bits in
the TFLG1 status register. If cleared, the corresponding flag is disabled from causing a hardware interrupt. If set,
the corresponding flag is enabled to cause a interrupt.
14.3.2.11 Timer System Control Register 2 (TSCR2)
Module Base + 0x000D
7
R
6
5
4
0
0
0
TOI
3
2
1
0
TCRE
PR2
PR1
PR0
0
0
0
0
W
Reset
0
0
0
0
= Unimplemented or Reserved
Figure 14-19. Timer System Control Register 2 (TSCR2)
Read: Anytime
Write: Anytime.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
487
Timer Module (TIM16B8CV2) Block Description
Table 14-13. TSCR2 Field Descriptions
Field
7
TOI
Description
Timer Overflow Interrupt Enable
0 Interrupt inhibited.
1 Hardware interrupt requested when TOF flag set.
3
TCRE
Timer Counter Reset Enable — This bit allows the timer counter to be reset by a successful output compare 7
event. This mode of operation is similar to an up-counting modulus counter.
0 Counter reset inhibited and counter free runs.
1 Counter reset by a successful output compare 7.
If TC7 = 0x0000 and TCRE = 1, TCNT will stay at 0x0000 continuously. If TC7 = 0xFFFF and TCRE = 1, TOF
will never be set when TCNT is reset from 0xFFFF to 0x0000.
2
PR[2:0]
Timer Prescaler Select — These three bits select the frequency of the timer prescaler clock derived from the
Bus Clock as shown in Table 14-14.
Table 14-14. Timer Clock Selection
PR2
PR1
PR0
Timer Clock
0
0
0
Bus Clock / 1
0
0
1
Bus Clock / 2
0
1
0
Bus Clock / 4
0
1
1
Bus Clock / 8
1
0
0
Bus Clock / 16
1
0
1
Bus Clock / 32
1
1
0
Bus Clock / 64
1
1
1
Bus Clock / 128
NOTE
The newly selected prescale factor will not take effect until the next
synchronized edge where all prescale counter stages equal zero.
14.3.2.12 Main Timer Interrupt Flag 1 (TFLG1)
Module Base + 0x000E
7
6
5
4
3
2
1
0
C7F
C6F
C5F
C4F
C3F
C2F
C1F
C0F
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-20. Main Timer Interrupt Flag 1 (TFLG1)
Read: Anytime
Write: Used in the clearing mechanism (set bits cause corresponding bits to be cleared). Writing a zero
will not affect current status of the bit.
S12P-Family Reference Manual, Rev. 1.13
488
Freescale Semiconductor
Timer Module (TIM16B8CV2) Block Description
Table 14-15. TRLG1 Field Descriptions
Field
Description
7:0
C[7:0]F
Input Capture/Output Compare Channel “x” Flag — These flags are set when an input capture or output
compare event occurs. Clearing requires writing a one to the corresponding flag bit while TEN or PAEN is set to
one.
When TFFCA bit in TSCR register is set, a read from an input capture or a write into an output compare channel
(0x0010–0x001F) will cause the corresponding channel flag CxF to be cleared.
14.3.2.13 Main Timer Interrupt Flag 2 (TFLG2)
Module Base + 0x000F
7
R
6
5
4
3
2
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
TOF
W
Reset
0
Unimplemented or Reserved
Figure 14-21. Main Timer Interrupt Flag 2 (TFLG2)
TFLG2 indicates when interrupt conditions have occurred. To clear a bit in the flag register, write the bit
to one while TEN bit of TSCR1 or PAEN bit of PACTL is set to one.
Read: Anytime
Write: Used in clearing mechanism (set bits cause corresponding bits to be cleared).
Any access to TCNT will clear TFLG2 register if the TFFCA bit in TSCR register is set.
Table 14-16. TRLG2 Field Descriptions
Field
Description
7
TOF
Timer Overflow Flag — Set when 16-bit free-running timer overflows from 0xFFFF to 0x0000. Clearing this bit
requires writing a one to bit 7 of TFLG2 register while the TEN bit of TSCR1 or PAEN bit of PACTL is set to one
(See also TCRE control bit explanation.)
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
489
Timer Module (TIM16B8CV2) Block Description
14.3.2.14 Timer Input Capture/Output Compare Registers High and Low 0–7
(TCxH and TCxL)
Module Base + 0x0010 = TC0H
0x0012 = TC1H
0x0014 = TC2H
0x0016 = TC3H
0x0018 = TC4H
0x001A = TC5H
0x001C = TC6H
0x001E = TC7H
15
14
13
12
11
10
9
0
Bit 15
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-22. Timer Input Capture/Output Compare Register x High (TCxH)
Module Base + 0x0011 = TC0L
0x0013 = TC1L
0x0015 = TC2L
0x0017 = TC3L
0x0019 = TC4L
0x001B = TC5L
0x001D = TC6L
0x001F = TC7L
7
6
5
4
3
2
1
0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-23. Timer Input Capture/Output Compare Register x Low (TCxL)
Depending on the TIOS bit for the corresponding channel, these registers are used to latch the value of the
free-running counter when a defined transition is sensed by the corresponding input capture edge detector
or to trigger an output action for output compare.
Read: Anytime
Write: Anytime for output compare function.Writes to these registers have no meaning or effect during
input capture. All timer input capture/output compare registers are reset to 0x0000.
NOTE
Read/Write access in byte mode for high byte should takes place before low
byte otherwise it will give a different result.
S12P-Family Reference Manual, Rev. 1.13
490
Freescale Semiconductor
Timer Module (TIM16B8CV2) Block Description
14.3.2.15 16-Bit Pulse Accumulator Control Register (PACTL)
Module Base + 0x0020
7
R
6
5
4
3
2
1
0
PAEN
PAMOD
PEDGE
CLK1
CLK0
PAOVI
PAI
0
0
0
0
0
0
0
0
W
Reset
0
Unimplemented or Reserved
Figure 14-24. 16-Bit Pulse Accumulator Control Register (PACTL)
When PAEN is set, the PACT is enabled.The PACT shares the input pin with IOC7.
Read: Any time
Write: Any time
Table 14-17. PACTL Field Descriptions
Field
6
PAEN
Description
Pulse Accumulator System Enable — PAEN is independent from TEN. With timer disabled, the pulse
accumulator can function unless pulse accumulator is disabled.
0 16-Bit Pulse Accumulator system disabled.
1 Pulse Accumulator system enabled.
5
PAMOD
Pulse Accumulator Mode — This bit is active only when the Pulse Accumulator is enabled (PAEN = 1). See
Table 14-18.
0 Event counter mode.
1 Gated time accumulation mode.
4
PEDGE
Pulse Accumulator Edge Control — This bit is active only when the Pulse Accumulator is enabled (PAEN = 1).
For PAMOD bit = 0 (event counter mode). See Table 14-18.
0 Falling edges on IOC7 pin cause the count to be incremented.
1 Rising edges on IOC7 pin cause the count to be incremented.
For PAMOD bit = 1 (gated time accumulation mode).
0 IOC7 input pin high enables M (bus clock) divided by 64 clock to Pulse Accumulator and the trailing falling
edge on IOC7 sets the PAIF flag.
1 IOC7 input pin low enables M (bus clock) divided by 64 clock to Pulse Accumulator and the trailing rising edge
on IOC7 sets the PAIF flag.
3:2
CLK[1:0]
Clock Select Bits — Refer to Table 14-19.
1
PAOVI
0
PAI
Pulse Accumulator Overflow Interrupt Enable
0 Interrupt inhibited.
1 Interrupt requested if PAOVF is set.
Pulse Accumulator Input Interrupt Enable
0 Interrupt inhibited.
1 Interrupt requested if PAIF is set.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
491
Timer Module (TIM16B8CV2) Block Description
Table 14-18. Pin Action
PAMOD
PEDGE
Pin Action
0
0
Falling edge
0
1
Rising edge
1
0
Div. by 64 clock enabled with pin high level
1
1
Div. by 64 clock enabled with pin low level
NOTE
If the timer is not active (TEN = 0 in TSCR), there is no divide-by-64
because the ÷64 clock is generated by the timer prescaler.
Table 14-19. Timer Clock Selection
CLK1
CLK0
Timer Clock
0
0
Use timer prescaler clock as timer counter clock
0
1
Use PACLK as input to timer counter clock
1
0
Use PACLK/256 as timer counter clock frequency
1
1
Use PACLK/65536 as timer counter clock frequency
For the description of PACLK please refer Figure 14-30.
If the pulse accumulator is disabled (PAEN = 0), the prescaler clock from the timer is always used as an
input clock to the timer counter. The change from one selected clock to the other happens immediately
after these bits are written.
14.3.2.16 Pulse Accumulator Flag Register (PAFLG)
Module Base + 0x0021
R
7
6
5
4
3
2
0
0
0
0
0
0
1
0
PAOVF
PAIF
0
0
W
Reset
0
0
0
0
0
0
Unimplemented or Reserved
Figure 14-25. Pulse Accumulator Flag Register (PAFLG)
Read: Anytime
Write: Anytime
When the TFFCA bit in the TSCR register is set, any access to the PACNT register will clear all the flags
in the PAFLG register. Timer module or Pulse Accumulator must stay enabled (TEN=1 or PAEN=1) while
clearing these bits.
S12P-Family Reference Manual, Rev. 1.13
492
Freescale Semiconductor
Timer Module (TIM16B8CV2) Block Description
Table 14-20. PAFLG Field Descriptions
Field
Description
1
PAOVF
Pulse Accumulator Overflow Flag — Set when the 16-bit pulse accumulator overflows from 0xFFFF to 0x0000.
Clearing this bit requires writing a one to this bit in the PAFLG register while TEN bit of TSCR1 or PAEN bit of
PACTL register is set to one.
0
PAIF
Pulse Accumulator Input edge Flag — Set when the selected edge is detected at the IOC7 input pin.In event
mode the event edge triggers PAIF and in gated time accumulation mode the trailing edge of the gate signal at
the IOC7 input pin triggers PAIF.
Clearing this bit requires writing a one to this bit in the PAFLG register while TEN bit of TSCR1 or PAEN bit of
PACTL register is set to one. Any access to the PACNT register will clear all the flags in this register when TFFCA
bit in register TSCR(0x0006) is set.
14.3.2.17 Pulse Accumulators Count Registers (PACNT)
Module Base + 0x0022
15
14
13
12
11
10
9
0
PACNT15
PACNT14
PACNT13
PACNT12
PACNT11
PACNT10
PACNT9
PACNT8
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-26. Pulse Accumulator Count Register High (PACNTH)
Module Base + 0x0023
7
6
5
4
3
2
1
0
PACNT7
PACNT6
PACNT5
PACNT4
PACNT3
PACNT2
PACNT1
PACNT0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-27. Pulse Accumulator Count Register Low (PACNTL)
Read: Anytime
Write: Anytime
These registers contain the number of active input edges on its input pin since the last reset.
When PACNT overflows from 0xFFFF to 0x0000, the Interrupt flag PAOVF in PAFLG (0x0021) is set.
Full count register access should take place in one clock cycle. A separate read/write for high byte and low
byte will give a different result than accessing them as a word.
NOTE
Reading the pulse accumulator counter registers immediately after an active
edge on the pulse accumulator input pin may miss the last count because the
input has to be synchronized with the bus clock first.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
493
Timer Module (TIM16B8CV2) Block Description
14.3.2.18 Output Compare Pin Disconnect Register(OCPD)
Module Base + 0x002C
7
6
5
4
3
2
1
0
OCPD7
OCPD6
OCPD5
OCPD4
OCPD3
OCPD2
OCPD1
OCPD0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-28. Ouput Compare Pin Disconnect Register (OCPD)
Read: Anytime
Write: Anytime
All bits reset to zero.
Table 14-21. OCPD Field Description
Field
OCPD[7:0}
Description
Output Compare Pin Disconnect Bits
0 Enables the timer channel port. Ouptut Compare action will occur on the channel pin. These bits do not affect
the input capture or pulse accumulator functions
1 Disables the timer channel port. Output Compare action will not occur on the channel pin, but the output
compare flag still become set .
14.3.2.19 Precision Timer Prescaler Select Register (PTPSR)
Module Base + 0x002E
7
6
5
4
3
2
1
0
PTPS7
PTPS6
PTPS5
PTPS4
PTPS3
PTPS2
PTPS1
PTPS0
0
0
0
0
0
0
0
0
R
W
Reset
Figure 14-29. Precision Timer Prescaler Select Register (PTPSR)
Read: Anytime
Write: Anytime
All bits reset to zero.
S12P-Family Reference Manual, Rev. 1.13
494
Freescale Semiconductor
Timer Module (TIM16B8CV2) Block Description
Table 14-22. PTPSR Field Descriptions
Field
Description
7:0
PTPS[7:0]
Precision Timer Prescaler Select Bits — These eight bits specify the division rate of the main Timer prescaler.
These are effective only when the PRNT bit of TSCR1 is set to 1. Table 14-23 shows some selection examples
in this case.
The newly selected prescale factor will not take effect until the next synchronized edge where all prescale counter
stages equal zero.
The Prescaler can be calculated as follows depending on logical value of the PTPS[7:0] and PRNT bit:
PRNT = 1 : Prescaler = PTPS[7:0] + 1
Table 14-23. Precision Timer Prescaler Selection Examples when PRNT = 1
PTPS7
PTPS6
PTPS5
PTPS4
PTPS3
PTPS2
PTPS1
PTPS0
Prescale
Factor
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
1
2
0
0
0
0
0
0
1
0
3
0
0
0
0
0
0
1
1
4
0
0
0
0
0
1
0
0
5
0
0
0
0
0
1
0
1
6
0
0
0
0
0
1
1
0
7
0
0
0
0
0
1
1
1
8
0
0
0
0
1
1
1
1
16
0
0
0
1
1
1
1
1
32
0
0
1
1
1
1
1
1
64
0
1
1
1
1
1
1
1
128
1
1
1
1
1
1
1
1
256
14.4
Functional Description
This section provides a complete functional description of the timer TIM16B8CV2 block. Please refer to
the detailed timer block diagram in Figure 14-30 as necessary.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
495
Timer Module (TIM16B8CV2) Block Description
Bus Clock
CLK[1:0]
PR[2:1:0]
channel 7 output
compare
PACLK
PACLK/256
PACLK/65536
MUX
TCRE
PRESCALER
CxI
TCNT(hi):TCNT(lo)
CxF
CLEAR COUNTER
16-BIT COUNTER
TOF
INTERRUPT
LOGIC
TOI
TE
TOF
CHANNEL 0
16-BIT COMPARATOR
OM:OL0
TC0
EDG0A
C0F
C0F
EDGE
DETECT
EDG0B
CH. 0 CAPTURE
IOC0 PIN
LOGIC CH. 0COMPARE
TOV0
IOC0 PIN
IOC0
CHANNEL 1
16-BIT COMPARATOR
EDG1A
C1F
C1F
OM:OL1
TC1
EDGE
DETECT
EDG1B
CH. 1 CAPTURE
IOC1 PIN
LOGIC CH. 1 COMPARE
TOV1
IOC1 PIN
IOC1
CHANNEL2
CHANNEL7
16-BIT COMPARATOR
TC7
OM:OL7
EDG7A
EDGE
DETECT
EDG7B
PAOVF
C7F
C7F
PACNT(hi):PACNT(lo)
TOV7
IOC7
PEDGE
PAE
PACLK/65536
CH.7 CAPTURE
IOC7 PIN PA INPUT
LOGIC CH. 7 COMPARE IOC7 PIN
EDGE
DETECT
16-BIT COUNTER
PACLK
PACLK/256
PAMOD
INTERRUPT
REQUEST
INTERRUPT
LOGIC
PAIF
DIVIDE-BY-64
PAOVI
PAI
PAOVF
PAIF
Bus Clock
PAOVF
PAOVI
Figure 14-30. Detailed Timer Block Diagram
14.4.1
Prescaler
The prescaler divides the bus clock by 1,2,4,8,16,32,64 or 128. The prescaler select bits, PR[2:0], select
the prescaler divisor. PR[2:0] are in timer system control register 2 (TSCR2).
S12P-Family Reference Manual, Rev. 1.13
496
Freescale Semiconductor
Timer Module (TIM16B8CV2) Block Description
The prescaler divides the bus clock by a prescalar value. Prescaler select bits PR[2:0] of in timer system
control register 2 (TSCR2) are set to define a prescalar value that generates a divide by 1, 2, 4, 8, 16, 32,
64 and 128 when the PRNT bit in TSCR1 is disabled.
By enabling the PRNT bit of the TSCR1 register, the performance of the timer can be enhanced. In this
case, it is possible to set additional prescaler settings for the main timer counter in the present timer by
using PTPSR[7:0] bits of PTPSR register.
14.4.2
Input Capture
Clearing the I/O (input/output) select bit, IOSx, configures channel x as an input capture channel. The
input capture function captures the time at which an external event occurs. When an active edge occurs on
the pin of an input capture channel, the timer transfers the value in the timer counter into the timer channel
registers, TCx.
The minimum pulse width for the input capture input is greater than two bus clocks.
An input capture on channel x sets the CxF flag. The CxI bit enables the CxF flag to generate interrupt
requests. Timer module or Pulse Accumulator must stay enabled (TEN bit of TSCR1 or PAEN bit of
PACTL regsiter must be set to one) while clearing CxF (writing one to CxF).
14.4.3
Output Compare
Setting the I/O select bit, IOSx, configures channel x as an output compare channel. The output compare
function can generate a periodic pulse with a programmable polarity, duration, and frequency. When the
timer counter reaches the value in the channel registers of an output compare channel, the timer can set,
clear, or toggle the channel pin if the corresponding OCPDx bit is set to zero. An output compare on
channel x sets the CxF flag. The CxI bit enables the CxF flag to generate interrupt requests. Timer module
or Pulse Accumulator must stay enabled (TEN bit of TSCR1 or PAEN bit of PACTL regsiter must be set
to one) while clearing CxF (writing one to CxF).
The output mode and level bits, OMx and OLx, select set, clear, toggle on output compare. Clearing both
OMx and OLx results in no output compare action on the output compare channel pin.
Setting a force output compare bit, FOCx, causes an output compare on channel x. A forced output
compare does not set the channel flag.
A channel 7 event, which can be a counter overflow when TTOV[7] is set or a successful output compare
on channel 7, overrides output compares on all other output compare channels. The output compare 7 mask
register masks the bits in the output compare 7 data register. The timer counter reset enable bit, TCRE,
enables channel 7 output compares to reset the timer counter. A channel 7 output compare can reset the
timer counter even if the IOC7 pin is being used as the pulse accumulator input.
Writing to the timer port bit of an output compare pin does not affect the pin state. The value written is
stored in an internal latch. When the pin becomes available for general-purpose output, the last value
written to the bit appears at the pin.
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Timer Module (TIM16B8CV2) Block Description
14.4.3.1
OC Channel Initialization
Internal register whose output drives OCx can be programmed before timer drives OCx. The desired state
can be programmed to this Internal register by writing a one to CFORCx bit with TIOSx, OCPDx and TEN
bits set to one. Setting OCPDx to zero allows Interal register to drive the programmed state to OCx. This
allows a glitch free switch over of port from general purpose I/O to timer output once the OCPDx bit is set
to zero.
14.4.4
Pulse Accumulator
The pulse accumulator (PACNT) is a 16-bit counter that can operate in two modes:
Event counter mode — Counting edges of selected polarity on the pulse accumulator input pin, PAI.
Gated time accumulation mode — Counting pulses from a divide-by-64 clock. The PAMOD bit selects the
mode of operation.
The minimum pulse width for the PAI input is greater than two bus clocks.
14.4.5
Event Counter Mode
Clearing the PAMOD bit configures the PACNT for event counter operation. An active edge on the IOC7
pin increments the pulse accumulator counter. The PEDGE bit selects falling edges or rising edges to
increment the count.
NOTE
The PACNT input and timer channel 7 use the same pin IOC7. To use the
IOC7, disconnect it from the output logic by clearing the channel 7 output
mode and output level bits, OM7 and OL7. Also clear the channel 7 output
compare 7 mask bit, OC7M7.
The Pulse Accumulator counter register reflect the number of active input edges on the PACNT input pin
since the last reset.
The PAOVF bit is set when the accumulator rolls over from 0xFFFF to 0x0000. The pulse accumulator
overflow interrupt enable bit, PAOVI, enables the PAOVF flag to generate interrupt requests.
NOTE
The pulse accumulator counter can operate in event counter mode even
when the timer enable bit, TEN, is clear.
14.4.6
Gated Time Accumulation Mode
Setting the PAMOD bit configures the pulse accumulator for gated time accumulation operation. An active
level on the PACNT input pin enables a divided-by-64 clock to drive the pulse accumulator. The PEDGE
bit selects low levels or high levels to enable the divided-by-64 clock.
The trailing edge of the active level at the IOC7 pin sets the PAIF. The PAI bit enables the PAIF flag to
generate interrupt requests.
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Timer Module (TIM16B8CV2) Block Description
The pulse accumulator counter register reflect the number of pulses from the divided-by-64 clock since the
last reset.
NOTE
The timer prescaler generates the divided-by-64 clock. If the timer is not
active, there is no divided-by-64 clock.
14.5
Resets
The reset state of each individual bit is listed within Section 14.3, “Memory Map and Register Definition”
which details the registers and their bit fields.
14.6
Interrupts
This section describes interrupts originated by the TIM16B8CV2 block. Table 14-24 lists the interrupts
generated by the TIM16B8CV2 to communicate with the MCU.
Table 14-24. TIM16B8CV1 Interrupts
Offset
(1)
Vector1
Priority1
Source
Description
C[7:0]F
—
—
—
Timer Channel 7–0
Active high timer channel interrupts 7–0
PAOVI
—
—
—
Pulse Accumulator
Input
Active high pulse accumulator input interrupt
PAOVF
—
—
—
Pulse Accumulator
Overflow
Pulse accumulator overflow interrupt
—
—
—
Timer Overflow
Timer Overflow interrupt
Interrupt
TOF
1. Chip Dependent.
The TIM16B8CV2 uses a total of 11 interrupt vectors. The interrupt vector offsets and interrupt numbers
are chip dependent.
14.6.1
Channel [7:0] Interrupt (C[7:0]F)
This active high outputs will be asserted by the module to request a timer channel 7 – 0 interrupt to be
serviced by the system controller.
14.6.2
Pulse Accumulator Input Interrupt (PAOVI)
This active high output will be asserted by the module to request a timer pulse accumulator input interrupt
to be serviced by the system controller.
14.6.3
Pulse Accumulator Overflow Interrupt (PAOVF)
This active high output will be asserted by the module to request a timer pulse accumulator overflow
interrupt to be serviced by the system controller.
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Timer Module (TIM16B8CV2) Block Description
14.6.4
Timer Overflow Interrupt (TOF)
This active high output will be asserted by the module to request a timer overflow interrupt to be serviced
by the system controller.
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Appendix A
Electrical Characteristics
A.1
General
This supplement contains the most accurate electrical information for the MC9S12P-Family
microcontroller available at the time of publication.
This introduction is intended to give an overview on several common topics like power supply, current
injection etc.
A.1.1
Parameter Classification
The electrical parameters shown in this supplement are guaranteed by various methods. To give the
customer a better understanding the following classification is used and the parameters are tagged
accordingly in the tables where appropriate.
NOTE
This classification is shown in the column labeled “C” in the parameter
tables where appropriate.
P:
C:
T:
D:
A.1.2
Those parameters are guaranteed during production testing on each individual device.
Those parameters are achieved by the design characterization by measuring a statistically relevant
sample size across process variations.
Those parameters are achieved by design characterization on a small sample size from typical
devices under typical conditions unless otherwise noted. All values shown in the typical column
are within this category.
Those parameters are derived mainly from simulations.
Power Supply
The VDDA, VSSA pin pairs supply the A/D converter and parts of the internal voltage regulator.
The VDDX, VSSX pin pairs [2:1] supply the I/O pins.
VDDR supplies the internal voltage regulator.
All VDDX pins are internally connected by metal.
All VSSX pins are internally connected by metal.
VDDA, VDDX and VSSA, VSSX are connected by diodes for ESD protection.
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Electrical Characteristics
NOTE
In the following context VDD35 is used for either VDDA, VDDR, and
VDDX; VSS35 is used for either VSSA and VSSX unless otherwise noted.
IDD35 denotes the sum of the currents flowing into the VDDA, VDDX and
VDDR pins.
A.1.3
Pins
There are four groups of functional pins.
A.1.3.1
I/O Pins
The I/O pins have a level in the range of 3.15V to 5.5V. This class of pins is comprised of all port I/O pins,
the analog inputs, BKGD and the RESET pins. Some functionality may be disabled.
A.1.3.2
Analog Reference
This group is made up by the VRH and VRL pins.
A.1.3.3
Oscillator
The pins EXTAL, XTAL dedicated to the oscillator have a nominal 1.8V level.
A.1.3.4
TEST
This pin is used for production testing only. The TEST pin must be tied to ground in all applications.
A.1.4
Current Injection
Power supply must maintain regulation within operating VDD35 or VDD range during instantaneous and
operating maximum current conditions. If positive injection current (Vin > VDD35) is greater than IDD35,
the injection current may flow out of VDD35 and could result in external power supply going out of
regulation. Ensure external VDD35 load will shunt current greater than maximum injection current. This
will be the greatest risk when the MCU is not consuming power; e.g., if no system clock is present, or if
clock rate is very low which would reduce overall power consumption.
A.1.5
Absolute Maximum Ratings
Absolute maximum ratings are stress ratings only. A functional operation under or outside those maxima
is not guaranteed. Stress beyond those limits may affect the reliability or cause permanent damage of the
device.
This device contains circuitry protecting against damage due to high static voltage or electrical fields;
however, it is advised that normal precautions be taken to avoid application of any voltages higher than
maximum-rated voltages to this high-impedance circuit. Reliability of operation is enhanced if unused
inputs are tied to an appropriate logic voltage level (e.g., either VSS35 or VDD35).
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Electrical Characteristics
Table A-1. Absolute Maximum Ratings(1)
Num
Rating
Symbol
Min
Max
Unit
1
I/O, regulator and analog supply voltage
VDD35
–0.3
6.0
V
2
Voltage difference VDDX to VDDA
∆VDDX
–6.0
0.3
V
3
Voltage difference VSSX to VSSA
∆VSSX
–0.3
0.3
V
4
Digital I/O input voltage
VIN
–0.3
6.0
V
5
Analog reference
VRH, VRL
–0.3
6.0
V
6
EXTAL, XTAL
VILV
–0.3
2.16
V
7
Instantaneous maximum current
Single pin limit for all digital I/O pins(2)
I
–25
+25
mA
8
Instantaneous maximum current
Single pin limit for EXTAL, XTAL
I
–25
+25
mA
–65
155
°C
D
DL
9
Storage temperature range
Tstg
1. Beyond absolute maximum ratings device might be damaged.
2. All digital I/O pins are internally clamped to VSSX and VDDX, or VSSA and VDDA.
A.1.6
ESD Protection and Latch-up Immunity
All ESD testing is in conformity with CDF-AEC-Q100 stress test qualification for automotive grade
integrated circuits. During the device qualification ESD stresses were performed for the Human Body
Model (HBM) and the Charge Device Model.
A device will be defined as a failure if after exposure to ESD pulses the device no longer meets the device
specification. Complete DC parametric and functional testing is performed per the applicable device
specification at room temperature followed by hot temperature, unless specified otherwise in the device
specification.
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Electrical Characteristics
Table A-2. ESD and Latch-up Test Conditions
Model
Description
Human Body
Latch-up
Symbol
Value
Unit
Series resistance
R1
1500
Ohm
Storage capacitance
C
100
pF
Number of pulse per pin
Positive
Negative
—
—
3
3
Minimum input voltage limit
—
–2.5
V
Maximum input voltage limit
—
7.5
V
Table A-3. ESD and Latch-Up Protection Characteristics
Num
C
1
C
2
3
4
A.1.7
Symbol
Min
Max
Unit
Human Body Model (HBM)
VHBM
2000
—
V
C
Charge Device Model (CDM)
VCDM
500
—
V
C
Latch-up current at TA = 125°C
Positive
Negative
ILAT
+100
–100
—
—
Latch-up current at TA = 27°C
Positive
Negative
ILAT
+200
–200
—
—
C
Rating
mA
mA
Operating Conditions
This section describes the operating conditions of the device. Unless otherwise noted those conditions
apply to all the following data.
NOTE
Please refer to the temperature rating of the device (C, V, M) with regards to
the ambient temperature TA and the junction temperature TJ. For power
dissipation calculations refer to Section A.1.8, “Power Dissipation and
Thermal Characteristics”.
Table A-4. Operating Conditions
Rating
Symbol
Min
Typ
Max
Unit
I/O, regulator and analog supply voltage
VDD35
3.13
5
5.5
V
Voltage difference VDDX to VDDA
∆VDDX
Voltage difference VDDR to VDDX
∆VDDR
Voltage difference VSSX to VSSA
∆VSSX
Voltage difference VSS3 , VSSPLL to VSSX
∆VSS
-0.1
0
0.1
V
Digital logic supply voltage
VDD
1.72
1.8
1.98
V
refer to Table A-14
-0.1
0
0.1
V
refer to Table A-14
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Electrical Characteristics
Table A-4. Operating Conditions
Oscillator
fosc
4
—
16
MHz
Bus frequency
fbus
0.5
—
32
MHz
Temperature Option C
Operating junction temperature range
Operating ambient temperature range(1)
TJ
TA
–40
–40
—
27
105
85
Temperature Option V
Operating junction temperature range
Operating ambient temperature range1
TJ
TA
–40
–40
—
27
125
105
°C
°C
Temperature Option M
°C
Operating junction temperature range
TJ
–40
—
150
Operating ambient temperature range1
TA
–40
27
125
1. Please refer to Section A.1.8, “Power Dissipation and Thermal Characteristics” for more details about the relation between
ambient temperature TA and device junction temperature TJ.
NOTE
Operation is guaranteed when powering down until low voltage reset
assertion.
A.1.8
Power Dissipation and Thermal Characteristics
Power dissipation and thermal characteristics are closely related. The user must assure that the maximum
operating junction temperature is not exceeded. The average chip-junction temperature (TJ) in °C can be
obtained from:
T
T
T
J
= Junction Temperature, [°C ]
A
= Ambient Temperature, [°C ]
P
D
Θ
J
= T + (P • Θ )
A
D
JA
= Total Chip Power Dissipation, [W]
= Package Thermal Resistance, [°C/W]
JA
The total power dissipation can be calculated from:
P
P
D
= P
INT
+P
IO
= Chip Internal Power Dissipation, [W]
2
P
=
R
⋅I
IO
DSON IO i
i
INT
∑
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Electrical Characteristics
PIO is the sum of all output currents on I/O ports associated with VDDX, whereby
R
R
V
OL
= ------------ ;for outputs driven low
DSON
I
OL
V
–V
DD35
OH
= -------------------------------------- ;for outputs driven high
DSON
I
OH
P
INT
= I
DDR
⋅V
DDR
+I
DDA
⋅V
DDA
Table A-5. Thermal Package Characteristics(1)
Num
C
Rating
Symbol
Min
Typ
Max
Unit
QFN 48
1
D
Thermal resistance QFN 48, single sided PCB(2)
θJA
—
—
82
°C/W
2
D
Thermal resistance QFN 48, double sided PCB
with 2 internal planes(3)
θJA
—
—
28
°C/W
3
D
Junction to Board QFN 48
θJB
—
—
11
°C/W
4
D
4
Junction to Case QFN 48
θJC
—
—
1.4
°C/W
5
D
Junction to Case (Bottom) QFN 485
ΨJT
—
—
4
°C/W
2
QFP 80
6
D
Thermal resistance QFP 80, single sided PCB
θJA
—
—
56
°C/W
7
D
Thermal resistance QFP 80, double sided PCB
with 2 internal planes3
θJA
—
—
43
°C/W
8
D
Junction to Board QFP 80
θJB
—
—
28
°C/W
9
D
Junction to Case QFP 80(4)
θJC
—
—
19
°C/W
10
D
Junction to Package Top QFP 80(5)
ΨJT
—
—
5
°C/W
LQFP 64
11
D
Thermal resistance LQFP 64, single sided PCB2
θJA
—
—
70
°C/W
12
D
Thermal resistance LQFP 64, double sided PCB
with 2 internal planes3
θJA
—
—
52
°C/W
13
D
Junction to Board LQFP 64
θJB
—
—
35
°C/W
14
D
Junction to Case LQFP 64(6)
θJC
—
—
17
°C/W
(7)
ΨJT
—
—
3
°C/W
15
D Junction to Package Top LQFP 64
1. The values for thermal resistance are achieved by package simulations
2. Junction to ambient thermal resistance, θJA was simulated to be equivalent to the JEDEC specification JESD51-2 in a
horizontal configuration in natural convection.
3. Junction to ambient thermal resistance, θJA was simulated to be equivalent to the JEDEC specification JESD51-7 in a
horizontal configuration in natural convection.
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Electrical Characteristics
4. Junction to case thermal resistance was simulated to be equivalent to the measured values using the cold plate technique with
the cold plate temperature used as the “case” temperature. This basic cold plate measurement technique is described by MILSTD 883D, Method 1012.1. This is the correct thermal metric to use to calculate thermal performance when the package is
being used with a heat sink.
5. Thermal characterization parameter ΨJT is the “resistance” from junction to reference point thermocouple on top center of the
case as defined in JESD51-2. ΨJT is a useful value to use to estimate junction temperature in a steady state customer
enviroment.
6. Junction to case thermal resistance was simulated to be equivalent to the measured values using the cold plate technique with
the cold plate temperature used as the “case” temperature. This basic cold plate measurement technique is described by MILSTD 883D, Method 1012.1. This is the correct thermal metric to use to calculate thermal performance when the package is
being used with a heat sink.
7. Thermal characterization parameter ΨJT is the “resistance” from junction to reference point thermocouple on top center of the
case as defined in JESD51-2. ΨJT is a useful value to use to estimate junction temperature in a steady state customer
enviroment.
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Electrical Characteristics
A.1.9
I/O Characteristics
This section describes the characteristics of all I/O pins except EXTAL, XTAL, TEST and supply pins.
Table A-6. 3.3-V I/O Characteristics
ALL 3.3V RANGE I/O PARAMETERS ARE SUBJECT TO CHANGE FOLLOWING CHARACTERIZATION
Conditions are 3.15 V < VDD35 < 3.6 V junction temperature from –40°C to +150°C, unless otherwise noted
I/O Characteristics for all I/O pins except EXTAL, XTAL,TEST and supply pins.
Num C
Symbol
Min
Typ
Max
Unit
P Input high voltage
VIH
0.65*VDD35
—
—
V
T Input high voltage
VIH
—
—
VDD35 + 0.3
V
P Input low voltage
VIL
—
—
0.35*VDD35
V
T Input low voltage
VIL
VSS35 – 0.3
—
—
V
3
C Input hysteresis
VHYS
4
Input leakage current (pins in high impedance input
mode)(1) Vin = VDD35 or VSS35
P M temperature range –40°C to +150°C
C V temperature range –40°C to +125°C
C C temperature range –40°C to +105°C
1
2
Rating
250
mV
µA
I
in
–1.00
-0.75
-0.50
—
—
—
1.00
0.75
0.50
5
C Output high voltage (pins in output mode)
Partial drive IOH = –0.75 mA
V
OH
VDD35 – 0.4
—
—
V
6
P Output high voltage (pins in output mode)
Full drive IOH = –4 mA
VOH
VDD35 – 0.4
—
—
V
7
C Output low voltage (pins in output mode)
Partial Drive IOL = +0.9 mA
VOL
—
—
0.4
V
8
P Output low voltage (pins in output mode)
Full Drive IOL = +4.75 mA
V
—
—
0.4
V
9
P Internal pull up resistance
VIH min > input voltage > VIL max
RPUL
25
—
50
KΩ
10
P Internal pull down resistance
VIH min > input voltage > VIL max
RPDH
25
—
50
KΩ
11
D Input capacitance
Cin
—
6
—
pF
T Injection current
Single pin limit
Total device limit, sum of all injected currents
IICS
IICP
–2.5
–25
P Port J, P interrupt input pulse filtered (STOP)(3)
tPULSE
—
—
3
µs
12
13
OL
(2)
3
—
mA
2.5
25
14
P Port J, P interrupt input pulse passed (STOP)
tPULSE
10
—
—
µs
15
D Port J, P interrupt input pulse filtered (STOP)
tPULSE
—
—
3
tcyc
16
D Port J, P interrupt input pulse passed (STOP)
tPULSE
4
—
—
tcyc
PWIRQ
1
—
—
tcyc
17 D IRQ pulse width, edge-sensitive mode (STOP)
1. Maximum leakage current occurs at maximum operating temperature. Current decreases by approximately one-half for each
8°C to 12 C° in the temperature range from 50°C to 125°C.
2. Refer to Section A.1.4, “Current Injection” for more details
3. Parameter only applies in stop or pseudo stop mode.
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Electrical Characteristics
Table A-7. 5-V I/O Characteristics
Conditions are 4.5 V < VDD35 < 5.5 V junction temperature from –40°C to +150°C, unless otherwise noted
I/O Characteristics for all I/O pins except EXTAL, XTAL,TEST and supply pins.
Num C
1
Rating
Symbol
Min
Typ
Max
Unit
0.65*VDD35
—
—
V
P Input high voltage
V
T Input high voltage
VIH
—
—
VDD35 + 0.3
V
P Input low voltage
VIL
—
—
0.35*VDD35
V
T Input low voltage
VIL
VSS35 – 0.3
—
—
V
3
C Input hysteresis
VHYS
250
—
mV
4
Input leakage current (pins in high impedance input
mode)(1) Vin = VDD35 or VSS35
P M temperature range –40°C to +150°C
C V temperature range –40°C to +125°C
C C temperature range –40°C to +105°C
2
IH
I
µA
in
–1.00
-0.75
-0.50
—
—
—
1.00
0.75
0.50
5
C Output high voltage (pins in output mode)
Partial drive IOH = –2 mA
V
OH
VDD35 – 0.8
—
—
V
6
P Output high voltage (pins in output mode)
Full drive IOH = –10 mA
VOH
VDD35 – 0.8
—
—
V
7
C Output low voltage (pins in output mode)
Partial drive IOL = +2 mA
VOL
—
—
0.8
V
8
P Output low voltage (pins in output mode)
Full drive IOL = +10 mA
V
—
—
0.8
V
9
P Internal pull up resistance
VIH min > input voltage > VIL max
RPUL
25
—
50
KΩ
10
P Internal pull down resistance
VIH min > input voltage > VIL max
RPDH
25
—
50
KΩ
11
D Input capacitance
Cin
—
6
—
pF
IICS
IICP
–2.5
–25
tPULSE
—
—
3
µs
12
13
OL
(2)
T Injection current
Single pin limit
Total device Limit, sum of all injected currents
P Port J, P interrupt input pulse filtered (STOP)(3)
3
—
mA
2.5
25
14
P Port J, P interrupt input pulse passed (STOP)
tPULSE
10
—
—
µs
15
D Port J, P interrupt input pulse filtered (STOP)
tPULSE
—
—
3
tcyc
16
D Port J, P interrupt input pulse passed (STOP)
tPULSE
4
—
—
tcyc
PWIRQ
1
—
—
tcyc
17 D IRQ pulse width, edge-sensitive mode (STOP)
1. Maximum leakage current occurs at maximum operating temperature. Current decreases by approximately one-half for each
8°C to 12 C° in the temperature range from 50°C to 125°C.
2. Refer to Section A.1.4, “Current Injection” for more details
3. Parameter only applies in stop or pseudo stop mode.
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Electrical Characteristics
A.1.10
Supply Currents
This section describes the current consumption characteristics of the device as well as the conditions for
the measurements.
A.1.10.1
Measurement Conditions
Run current is measured on VDDR pin. It does not include the current to drive external loads. Unless
otherwise noted the currents are measured in special single chip mode and the CPU code is executed from
RAM. For Run and Wait current measurements PLL is on and the reference clock is the IRC1M trimmed
to 1MHz. The bus frequency is 32MHz and the CPU frequency is 64MHz. Table A-8., Table A-9. and
Table A-10. show the configuration of the CPMU module and the peripherals for Run, Wait and Stop
current measurement.
Table A-8. CPMU Configuration for Pseudo Stop Current Measurement
CPMU REGISTER
Bit settings/Conditions
CPMUCLKS
PLLSEL=0, PSTP=1,
PRE=PCE=RTIOSCSEL=COPOSCSEL=1
CPMUOSC
OSCE=1, External Square wave on EXTAL fEXTAL=16MHz,
VIH= 1.8V, VIL=0V
CPMURTI
RTDEC=0, RTR[6:4]=111, RTR[3:0]=1111;
CPMUCOP
WCOP=1, CR[2:0]=111
Table A-9. CPUM Configuration for Run/Wait and Full Stop Current Measurement
CPMU REGISTER
CPMUSYNR
CPMUPOSTDIV
Bit settings/Conditions
VCOFRQ[1:0]=01,SYNDIV[5:0] = 32
POSTDIV[4:0]=0,
CPMUCLKS
PLLSEL=1
CPMUOSC
OSCE=0,
Reference clock for PLL is fref=firc1m trimmed to 1MHz
API settings for STOP current measurement
CPMUAPICTL
APIEA=0, APIFE=1, APIE=0
CPMUAPITR
trimmed to 10Khz
CPMUAPIRH/RL
set to $FFFF
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Freescale Semiconductor
Electrical Characteristics
Table A-10. Peripheral Configurations for Run & Wait Current Measurement
Peripheral
MSCAN
Configuration
configured to loop-back mode using a bit rate of 1Mbit/s
SPI
configured to master mode, continously transmit data (0x55
or 0xAA) at 1Mbit/s
SCI
configured into loop mode, continously transmit data (0x55)
at speed of 57600 baud
PWM
configured to toggle its pins at the rate of 40kHz
ATD
the peripheral is configured to operate at its maximum specified frequency and to continuously convert voltages on all
input channels in sequence.
DBG
the module is enabled and the comparators are configured
to trigger in outside range.The range covers all the code
executed by the core.
TIM
the peripheral shall be configured to output compare mode,
pulse accumulator and modulus counter enabled.
COP & RTI
enabled
Table A-11. Run and Wait Current Characteristics
Conditions are: VDDR=5.5V, TA=125°C, see Table A-9. and Table A-10.
Num
C
Rating
1
P
IDD Run Current
2
P
IDD Wait Current
Symbol
Min
Typ
Max
Unit
IDDR
18
20
mA
IDDW
11
12
mA
Typ
Max
Unit
Table A-12. Full Stop Current Characteristics
Conditions are: VDDR=5.5V, API see Table A-9.
Num
C
Rating
Symbol
Min
Stop Current API disabled
1
P
150°C
IDDS
250
1100
µA
2
P
-40°C
IDDS
15
35
µA
3
P
25°C,
IDDS
25
50
µA
Stop Current API enabled
4
C
150°C,
IDDS
270
µA
5
C
-40°C
IDDS
20
µA
6
C
25°C
IDDS
40
µA
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Electrical Characteristics
Table A-13. Pseudo Stop Current Characteristics
Conditions are: VDDR=5.5V, RTI and COP and API enabled, see Table A-8.
Num
C
1
C
150°C
IDDPS
450
µA
2
C
-40°C
IDDPS
175
µA
3
C
25°C
IDDPS
200
µA
A.2
Rating
Symbol
Min
Typ
Max
Unit
ATD Characteristics
This section describes the characteristics of the analog-to-digital converter.
A.2.1
ATD Operating Characteristics
The Table A-14 and Table A-15 show conditions under which the ATD operates.
The following constraints exist to obtain full-scale, full range results:
VSSA ≤ VRL ≤ VIN ≤ VRH ≤ VDDA.
This constraint exists since the sample buffer amplifier can not drive beyond the power supply levels that
it ties to. If the input level goes outside of this range it will effectively be clipped.
Table A-14. ATD Operating Characteristics
Conditions are shown in Table A-4 unless otherwise noted, supply voltage 3.13 V < VDDA < 5.5 V
Num C
1
Rating
D Reference potential
Low
High
Symbol
Min
Typ
Max
Unit
VRL
VRH
VSSA
VDDA/2
—
—
VDDA/2
VDDA
V
V
2
D Voltage difference VDDX to VDDA
∆VDDX
–2.35
0
0.1
V
3
D Voltage difference VSSX to VSSA
∆VSSX
–0.1
0
0.1
V
VRH-VRL
3.13
5.0
5.5
V
8.0
MHz
(1)
4
C Differential reference voltage
5
C ATD Clock Frequency (derived from bus clock via the
prescaler bus)
6
P ATD Clock Frequency in Stop mode (internal generated
temperature and voltage dependent clock, ICLK)
7
D ADC conversion in stop, recovery time(2)
0.25
fATDCLk
tATDSTPRC
0.6
1
1.7
MHz
—
—
1.5
us
42
41
39
ATD
clock
Cycles
V
8
ATD Conversion Period(3)
12 bit resolution:
D 10 bit resolution:
8 bit resolution:
NCONV12
NCONV10
NCONV8
20
19
17
1. Full accuracy is not guaranteed when differential voltage is less than 4.50 V
2. When converting in Stop Mode (ICLKSTP=1) an ATD Stop Recovery time tATDSTPRCV is required to switch back to bus clock
based ATDCLK when leaving Stop Mode. Do not access ATD registers during this time.
3. The minimum time assumes a sample time of 4 ATD clock cycles. The maximum time assumes a sample time of 24 ATD clock
cycles and the discharge feature (SMP_DIS) enabled, which adds 2 ATD clock cycles.
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Electrical Characteristics
A.2.2
Factors Influencing Accuracy
Source resistance, source capacitance and current injection have an influence on the accuracy of the ATD.
A further factor is that PortAD pins that are configured as output drivers switching.
A.2.2.1
Port AD Output Drivers Switching
PortAD output drivers switching can adversely affect the ATD accuracy whilst converting the analog
voltage on other PortAD pins because the output drivers are supplied from the VDDA/VSSA ATD supply
pins. Although internal design measures are implemented to minimize the affect of output driver noise, it
is recommended to configure PortAD pins as outputs only for low frequency, low load outputs. The impact
on ATD accuracy is load dependent and not specified. The values specified are valid under condition that
no PortAD output drivers switch during conversion.
A.2.2.2
Source Resistance
Due to the input pin leakage current as specified in Table A-6 and Table A-7 in conjunction with the source
resistance there will be a voltage drop from the signal source to the ATD input. The maximum source
resistance RS specifies results in an error (10-bit resolution) of less than 1/2 LSB (2.5 mV) at the maximum
leakage current. If device or operating conditions are less than worst case or leakage-induced error is
acceptable, larger values of source resistance of up to 10Kohm are allowed.
A.2.2.3
Source Capacitance
When sampling an additional internal capacitor is switched to the input. This can cause a voltage drop due
to charge sharing with the external and the pin capacitance. For a maximum sampling error of the input
voltage ≤ 1LSB (10-bit resilution), then the external filter capacitor, Cf ≥ 1024 * (CINS–CINN).
A.2.2.4
Current Injection
There are two cases to consider.
1. A current is injected into the channel being converted. The channel being stressed has conversion
values of $3FF (in 10-bit mode) for analog inputs greater than VRH and $000 for values less than
VRL unless the current is higher than specified as disruptive condition.
2. Current is injected into pins in the neighborhood of the channel being converted. A portion of this
current is picked up by the channel (coupling ratio K), This additional current impacts the accuracy
of the conversion depending on the source resistance.
The additional input voltage error on the converted channel can be calculated as:
VERR = K * RS * IINJ
with IINJ being the sum of the currents injected into the two pins adjacent to the converted channel.
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513
Electrical Characteristics
Table A-15. ATD Electrical Characteristics
Conditions are shown in Table A-4 unless otherwise noted
Num C
Rating
Symbol
Min
Typ
Max
Unit
RS
—
—
1
KΩ
1
C Max input source resistance(1)
2
D Total input capacitance Non sampling
Total input capacitance Sampling
CINN
CINS
—
—
—
—
10
16
pF
3
D Input internal Resistance
RINA
-
5
15
kΩ
4
C Disruptive analog input current
INA
-2.5
—
2.5
mA
5
C Coupling ratio positive current injection
Kp
—
—
1E-4
A/A
6
C Coupling ratio negative current injection
Kn
1. 1 Refer to A.2.2.2 for further information concerning source resistance
—
—
5E-3
A/A
A.2.3
ATD Accuracy
Table A-16. and Table A-17. specifies the ATD conversion performance excluding any errors due to
current injection, input capacitance and source resistance.
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Freescale Semiconductor
Electrical Characteristics
A.2.3.1
ATD Accuracy Definitions
For the following definitions see also Figure A-1.
Differential non-linearity (DNL) is defined as the difference between two adjacent switching steps.
V –V
i
i–1
DNL ( i ) = --------------------------- – 1
1LSB
The integral non-linearity (INL) is defined as the sum of all DNLs:
n
INL ( n ) =
∑
V –V
n
0
DNL ( i ) = --------------------- – n
1LSB
i=1
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515
Electrical Characteristics
DNL
Vi-1
10-Bit Absolute Error Boundary
LSB
Vi
$3FF
8-Bit Absolute Error Boundary
$3FE
$3FD
$FF
$3FC
$3FB
$3FA
$3F9
$FE
$3F8
$3F7
$3F6
$3F5
10-Bit Resolution
$3F3
9
Ideal Transfer Curve
2
8
8-Bit Resolution
$FD
$3F4
7
10-Bit Transfer Curve
6
5
1
4
3
8-Bit Transfer Curve
2
1
0
5
10
15
20
25
30
35
40
45
55
60
65
70
75
80
85
90
95 100 105 110 115 120
5000 +
Vin
mV
Figure A-1. ATD Accuracy Definitions
NOTE
Figure A-1 shows only definitions, for specification values refer to Table A16 and Table A-17.
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Electrical Characteristics
Table A-16. ATD Conversion Performance 5V range
Conditions are shown in Table A-4. unless otherwise noted. VREF = VRH - VRL = 5.12V. fATDCLK = 8.0MHz
The values are tested to be valid with no PortAD output drivers switching simultaneous with conversions.
Rating(1)
Num C
Symbol
Min
Typ
Max
1
P Resolution
12-Bit
LSB
2
P Differential Nonlinearity
12-Bit
DNL
-4
±2
4
counts
3
P Integral Nonlinearity
12-Bit
INL
-5
±2.5
5
counts
12-Bit
AE
-7
±4
7
counts
(2)
1.25
Unit
mV
4
P Absolute Error
5
C Resolution
10-Bit
LSB
6
C Differential Nonlinearity
10-Bit
DNL
-1
±0.5
1
counts
7
C Integral Nonlinearity
10-Bit
INL
-2
±1
2
counts
8
C Absolute Error2.
10-Bit
AE
-3
±2
3
counts
9
C Resolution
8-Bit
LSB
10
C Differential Nonlinearity
8-Bit
DNL
-0.5
±0.3
0.5
counts
11
C Integral Nonlinearity
8-Bit
INL
-1
±0.5
1
counts
5
mV
20
mV
8-Bit
AE
-1.5
±1
1.5
counts
12 C Absolute Error2.
1. The 8-bit and 10-bit mode operation is structurally tested in production test. Absolute values are tested in 12-bit mode.
2. These values include the quantization error which is inherently 1/2 count for any A/D converter.
Table A-17. ATD Conversion Performance 3.3V range
Conditions are shown in Table A-4. unless otherwise noted. VREF = VRH - VRL = 3.3V. fATDCLK = 8.0MHz
The values are tested to be valid with no PortAD output drivers switching simultaneous with conversions.
Rating(1)
Num C
Symbol
Min
Typ
Max
1
P Resolution
12-Bit
LSB
2
P Differential Nonlinearity
12-Bit
DNL
-6
±3
6
counts
3
P Integral Nonlinearity
12-Bit
INL
-7
±3
7
counts
-8
±4
8
counts
(2)
0.80
Unit
mV
4
P Absolute Error
12-Bit
AE
5
C Resolution
10-Bit
LSB
6
C Differential Nonlinearity
10-Bit
DNL
-1.5
±1
1.5
counts
7
C Integral Nonlinearity
10-Bit
INL
-2
±1
2
counts
-3
±2
3
counts
2.
3.22
mV
8
C Absolute Error
10-Bit
AE
9
C Resolution
8-Bit
LSB
10
C Differential Nonlinearity
8-Bit
DNL
-0.5
±0.3
0.5
counts
11
C Integral Nonlinearity
8-Bit
INL
-1
±0.5
1
counts
12.89
mV
2.
8-Bit
AE
-1.5
±1
1.5
counts
12 C Absolute Error
1. The 8-bit and 10-bit mode operation is structurally tested in production test. Absolute values are tested in 12-bit mode.
2. These values include the quantization error which is inherently 1/2 count for any A/D converter.
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Electrical Characteristics
A.3
A.3.1
NVM
Timing Parameters
The time base for all NVM program or erase operations is derived from the bus clock using the FCLKDIV
register. The frequency of this derived clock must be set within the limits specified as fNVMOP. The NVM
module does not have any means to monitor the frequency and will not prevent program or erase operation
at frequencies above or below the specified minimum. When attempting to program or erase the NVM
module at a lower frequency, a full program or erase transition is not assured.
The following sections provide equations which can be used to determine the time required to execute
specific flash commands. All timing parameters are a function of the bus clock frequency, fNVMBUS. All
program and erase times are also a function of the NVM operating frequency, fNVMOP. A summary of key
timing parameters can be found in Table A-18.
A.3.1.1
Erase Verify All Blocks (Blank Check) (FCMD=0x01)
The time required to perform a blank check on all blocks is dependent on the location of the first non-blank
word starting at relative address zero. It takes one bus cycle per phrase to verify plus a setup of the
command. Assuming that no non-blank location is found, then the time to erase verify all blocks is given
by:
1
t check = 35500 ⋅ --------------------f NVMBUS
A.3.1.2
Erase Verify Block (Blank Check) (FCMD=0x02)
The time required to perform a blank check is dependent on the location of the first non-blank word starting
at relative address zero. It takes one bus cycle per phrase to verify plus a setup of the command.
Assuming that no non-blank location is found, then the time to erase verify a P-Flash block is given by:
1
t pcheck = 33500 ⋅ --------------------f NVMBUS
Assuming that no non-blank location is found, then the time to erase verify a D-Flash block is given by:
1
t dcheck = 2800 ⋅ --------------------f NVMBUS
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Freescale Semiconductor
Electrical Characteristics
A.3.1.3
Erase Verify P-Flash Section (FCMD=0x03)
The maximum time to erase verify a section of P-Flash depends on the number of phrases being verified
(NVP) and is given by:
1
t ≈ ( 450 + N VP ) ⋅ --------------------f NVMBUS
A.3.1.4
Read Once (FCMD=0x04)
The maximum read once time is given by:
1
t = 400 ⋅ --------------------f NVMBUS
A.3.1.5
Program P-Flash (FCMD=0x06)
The programming time for a single phrase of four P-Flash words and the two seven-bit ECC fields is
dependent on the bus frequency, fNVMBUS, as well as on the NVM operating frequency, fNVMOP.
The typical phrase programming time is given by:
1
1
t ppgm ≈ 164 ⋅ ------------------- + 2000 ⋅ --------------------f NVMBUS
f NVMOP
The maximum phrase programming time is given by:
1
1
t ppgm ≈ 164 ⋅ ------------------- + 2500 ⋅ --------------------f NVMBUS
f NVMOP
A.3.1.6
Program Once (FCMD=0x07)
The maximum time required to program a P-Flash Program Once field is given by:
1
1
t ≈ 164 ⋅ ------------------- + 2150 ⋅ --------------------f NVMBUS
f NVMOP
A.3.1.7
Erase All Blocks (FCMD=0x08)
The time required to erase all blocks is given by:
1
1
t mass ≈ 100100 ⋅ ------------------- + 70000 ⋅ --------------------f NVMBUS
f NVMOP
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Electrical Characteristics
A.3.1.8
Erase P-Flash Block (FCMD=0x09)
The time required to erase the P-Flash block is given by:
1
1
t pmass ≈ 100100 ⋅ ------------------- + 67000 ⋅ --------------------f NVMBUS
f NVMOP
A.3.1.9
Erase P-Flash Sector (FCMD=0x0A)
The typical time to erase a 512-byte P-Flash sector is given by:
1
1
t pera ≈ 20020 ⋅ ------------------- + 700 ⋅ --------------------f NVMBUS
f NVMOP
The maximum time to erase a 512-byte P-Flash sector is given by:
1
1
t pera ≈ 20020 ⋅ ------------------- + 1400 ⋅ --------------------f NVMOP
f NVMBUS
A.3.1.10
Unsecure Flash (FCMD=0x0B)
The maximum time required to erase and unsecure the Flash is given by:
for 128 Kbyte P-Flash and 4 Kbyte D-Flash
1
1
t uns ≈ 100100 ⋅ ------------------- + 70000 ⋅ --------------------f NVMBUS
f NVMOP
A.3.1.11
Verify Backdoor Access Key (FCMD=0x0C)
The maximum verify backdoor access key time is given by:
1
t = 400 ⋅ --------------------f NVMBUS
A.3.1.12
Set User Margin Level (FCMD=0x0D)
The maximum set user margin level time is given by:
1
t = 350 ⋅ --------------------f NVMBUS
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Freescale Semiconductor
Electrical Characteristics
A.3.1.13
Set Field Margin Level (FCMD=0x0E)
The maximum set field margin level time is given by:
1
t = 350 ⋅ --------------------f NVMBUS
A.3.1.14
Erase Verify D-Flash Section (FCMD=0x10)
The time required to Erase Verify D-Flash for a given number of words NW is given by:
1
t dcheck ≈ ( 450 + N W ) ⋅ --------------------f NVMBUS
A.3.1.15
Program D-Flash (FCMD=0x11)
D-Flash programming time is dependent on the number of words being programmed and their location
with respect to a row boundary since programming across a row boundary requires extra steps. The DFlash programming time is specified for different cases: 1,2,3,4 words and 4 words across a row boundary.
The typical D-Flash programming time is given by the following equation, where NW denotes the number
of words; BC=0 if no row boundary is crossed and BC=1 if a row boundary is crossed:
1
1
t dpgm ≈ ⎛ ( 14 + ( 54 ⋅ N W ) + ( 14 ⋅ BC ) ) ⋅ ------------------- ⎞ + ⎛ ( 500 + ( 525 ⋅ N W ) + ( 100 ⋅ BC ) ) ⋅ --------------------- ⎞
⎝
f NVMOP ⎠ ⎝
f NVMBUS ⎠
The maximum D-Flash programming time is given by:
1
1
t dpgm ≈ ⎛ ( 14 + ( 54 ⋅ N W ) + ( 14 ⋅ BC ) ) ⋅ ------------------- ⎞ + ⎛ ( 500 + ( 750 ⋅ N W ) + ( 100 ⋅ BC ) ) ⋅ --------------------- ⎞
⎝
f NVMOP ⎠ ⎝
f NVMBUS ⎠
A.3.1.16
Erase D-Flash Sector (FCMD=0x12)
Typical D-Flash sector erase times, expected on a new device where no margin verify fails occur, is given
by:
1
1
t dera ≈ 5025 ⋅ ------------------- + 700 ⋅ --------------------f NVMBUS
f NVMOP
Maximum D-Flash sector erase times is given by:
1
1
t dera ≈ 20100 ⋅ ------------------- + 3400 ⋅ --------------------f NVMBUS
f NVMOP
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Freescale Semiconductor
521
Electrical Characteristics
The D-Flash sector erase time is ~5ms on a new device and can extend to ~20ms as the flash is cycled.
Table A-18. NVM Timing Characteristics (FTMRC)
Num C
Rating
Symbol
Min
Typ(1)
Max(2)
Unit(3)
1
Bus frequency
fNVMBUS
1
—
32
MHz
2
Operating frequency
fNVMOP
0.8
1.0
1.05
MHz
3
D Erase all blocks (mass erase) time
tmass
—
100
130
ms
4
D Erase verify all blocks (blank check) time
tcheck
—
—
35500
tcyc
5
D Unsecure Flash time
tuns
—
100
130
ms
6
D P-Flash block erase time
tpmass
—
100
130
ms
7
D P-Flash erase verify (blank check) time
tpcheck
—
—
33500
tcyc
8
D P-Flash sector erase time
tpera
—
20
26
ms
9
D P-Flash phrase programming time
tppgm
—
226
285
µs
tdera
—
(4)
5
26
ms
10
D D-Flash sector erase time
11
D D-Flash erase verify (blank check) time
tdcheck
—
—
2800
tcyc
12a
D D-Flash one word programming time
tdpgm1
—
100
107
µs
12b
D D-Flash two word programming time
tdpgm2
—
170
185
µs
12c
D D-Flash three word programming time
tdpgm3
—
241
262
µs
12d
D D-Flash four word programming time
tdpgm4
—
311
339
µs
328
357
µs
—
D D-Flash four word programming time crossing row
tdpgm4c
boundary
1. Typical program and erase times are based on typical fNVMOP and maximum fNVMBUS
2. Maximum program and erase times are based on minimum fNVMOP and maximum fNVMBUS
3. tcyc = 1 / fNVMBUS
4. Typical value for a new device
12e
A.3.2
NVM Reliability Parameters
The reliability of the NVM blocks is guaranteed by stress test during qualification, constant process
monitors and burn-in to screen early life failures.
The data retention and program/erase cycling failure rates are specified at the operating conditions noted.
The program/erase cycle count on the sector is incremented every time a sector or mass erase event is
executed.
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Freescale Semiconductor
Electrical Characteristics
NOTE
All values shown in Table A-19 are preliminary and subject to further
characterization.
Table A-19. NVM Reliability Characteristics
Conditions are shown in Table A-4 unless otherwise noted
Num C
Rating
Symbol
Min
Typ
Max
Unit
tNVMRET
20
100(2)
—
Years
nFLPE
10K
100K(3)
—
Cycles
Program Flash Arrays
1
C Data retention at an average junction temperature of TJavg =
85°C(1) after up to 10,000 program/erase cycles
2
C Program Flash number of program/erase cycles
(-40°C ≤ tj ≤ 150°C)
Data Flash Array
3
C Data retention at an average junction temperature of TJavg =
85°C1 after up to 50,000 program/erase cycles
tNVMRET
5
1002
—
Years
4
C Data retention at an average junction temperature of TJavg =
85°C1 after up to 10,000 program/erase cycles
tNVMRET
10
1002
—
Years
5
C Data retention at an average junction temperature of TJavg =
85°C1 after less than 100 program/erase cycles
tNVMRET
20
1002
—
Years
6
C Data Flash number of program/erase cycles (-40°C ≤ tj ≤ 150°C)
nFLPE
50K
500K3
—
Cycles
1. TJavg does not exceed 85°C in a typical temperature profile over the lifetime of a consumer, industrial or automotive
application.
2. Typical data retention values are based on intrinsic capability of the technology measured at high temperature and de-rated
to 25°C using the Arrhenius equation. For additional information on how Freescale defines Typical Data Retention, please
refer to Engineering Bulletin EB618
3. Spec table quotes typical endurance evaluated at 25°C for this product family. For additional information on how Freescale
defines Typical Endurance, please refer to Engineering Bulletin EB619.
A.4
A.4.1
Phase Locked Loop
Jitter Definitions
With each transition of the feedback clock, the deviation from the reference clock is measured and input
voltage to the VCO is adjusted accordingly.The adjustment is done continuously with no abrupt changes
in the VCOCLK frequency. Noise, voltage, temperature and other factors cause slight variations in the
control loop resulting in a clock jitter. This jitter affects the real minimum and maximum clock periods as
illustrated in Figure A-2.
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523
Electrical Characteristics
1
0
2
3
N-1
N
tmin1
tnom
tmax1
tminN
tmaxN
Figure A-2. Jitter Definitions
The relative deviation of tnom is at its maximum for one clock period, and decreases towards zero for larger
number of clock periods (N).
Defining the jitter as:
t
(N)
t
(N) ⎞
⎛
max
min
J ( N ) = max ⎜ 1 – ----------------------- , 1 – ----------------------- ⎟
N⋅t
N⋅t
⎝
nom
nom ⎠
For N < 100, the following equation is a good fit for the maximum jitter:
j
1
J ( N ) = -------N
J(N)
1
5
10
20
N
Figure A-3. Maximum Bus Clock Jitter Approximation
NOTE
On timers and serial modules a prescaler will eliminate the effect of the jitter
to a large extent.
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Freescale Semiconductor
Electrical Characteristics
A.4.2
Electrical Characteristics for the PLL
Table A-20. PLL Characteristics
Conditions are shown in Table A-4 unless otherwise noted
Num C
Rating
Symbol
Min
fVCORST
Typ
Max
Unit
8
32
MHz
64
MHz
1
D VCO frequency during system reset
2
C VCO locking range
fVCO
32
3
C Reference Clock
fREF
1
4
D Lock Detection
|∆Lock|
0
1.5
%(1)
6
D Un-Lock Detection
|∆unl|
0.5
2.5
%1
7
C Time to lock
tlock
150 +
256/fREF
µs
MHz
j1
8
C Jitter fit parameter 1(2)
1.4
%
1. % deviation from target frequency
2. fREF = 4MHz oscillator, fBUS = 32MHz equivalent fPLL = 64MHz, CPMUREFDIV=$40, CPMUSYNR=$47, CPMUPOSTDIV=$00
A.5
Electrical Characteristics for the IRC1M
Table A-21. IRC1M Characteristics
Conditions are shown in Table A-4 unless otherwise noted
Num C
1
Rating
P Junction Temperature -40°C to 150°C
Internal Reference Frequency, factory trimmed
Symbol
Min
Typ
Max
Unit
fIRC1M_TRIM
0.985
1
1.015
MHz
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Freescale Semiconductor
525
Electrical Characteristics
A.6
Electrical Characteristics for the Oscillator (OSCLCP)
Table A-22. OSCLCP Characteristics
Conditions are shown in Table A-4 unless otherwise noted
Num C
Rating
Symbol
Min
Typ
Max
Unit
16
MHz
1
C Crystal oscillator range
fOSC
4.0
2
P Startup Current
iOSC
100
3a
C Oscillator start-up time (LCP, 4MHz)(1)
tUPOSC
—
2
10
ms
3b
C Oscillator start-up time (LCP, 8MHz)1
tUPOSC
—
1.6
8
ms
3c
C Oscillator start-up time (LCP, 16MHz)1
tUPOSC
—
1
5
ms
4
P Clock Monitor Failure Assert Frequency
fCMFA
200
400
1000
KHz
5
D Input Capacitance (EXTAL, XTAL pins)
CIN
6
C EXTAL Pin Input Hysteresis
VHYS,EXTAL
µA
7
—
pF
180
—
mV
EXTAL Pin oscillation amplitude (loop
—
—
VPP,EXTAL
0.9
V
controlled Pierce)
1. These values apply for carefully designed PCB layouts with capacitors that match the crystal/resonator requirements.
7
A.7
C
Reset Characteristics
Table A-23. Reset and Stop & Startup Characteristics
Conditions are shown in Table A-4 unless otherwise noted
Num C
1
Rating
C Reset input pulse width, minimum input time
Symbol
Min
PWRSTL
2
Typ
Max
Unit
tVCORS
T
2
C Startup from Reset
nRST
768
tVCORS
T
3
C STOP recovery time
tSTP_REC
50
µs
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526
Freescale Semiconductor
Electrical Characteristics
A.8
Electrical Specification for Voltage Regulator
Table A-24. IVREG Characteristics
Num
C
Characteristic
Symbol
Min
Typical
Max
Unit
1
P
Input Voltages
VVDDR,A
3.13
—
5.5
V
2
P
VDDA Low Voltage Interrupt Assert Level (1)
VDDA Low Voltage Interrupt Deassert Level
VLVIA
VLVID
4.04
4.19
4.23
4.38
4.40
4.49
V
V
3
P
VDDX Low Voltage Reset Deassert (2) (3)
VLVRXD
—
—
3.13
V
4
T
API ACLK frequency
(APITR[5:0] = %000000)
fACLK
—
10
—
KHz
5
C
Trimmed API internal clock(4) ∆f / fnominal
dfACLK
- 5%
—
+ 5%
—
6
D
The first period after enabling the counter
by APIFE might be reduced by API start up
delay
tsdel
—
—
100
us
7
T
Temperature Sensor Slope
dVTS
4.0
5.5
6.5
mV/
oC
High Temperature Interrupt Assert
THTIA
125
oC
(CPMUHTTR=$88)(5)
105
8
T
THTID
High Temperature Interrupt Deassert
(CPMUHTTR=$88)
1. Monitors VDDA, active only in Full Performance Mode. Indicates I/O & ADC performance degradation due to low supply
voltage.
2. Device functionality is guaranteed on power down to the LVR assert level
3. Monitors VDDX, active only in Full Performance Mode. MCU is monitored by the POR in RPM (see Figure A-4)
4. The API Trimming APITR[5:0] bits must be set so that fACLK=10KHz.
5. A hysteresis is guaranteed by design
NOTE
The LVR monitors the voltages VDD, VDDF and VDDX. As soon as voltage
drops on these supplies which would prohibit the correct function of the
microcontroller, the LVR is triggering a reset.
A.9
Chip Power-up and Voltage Drops
LVI (low voltage interrupt), POR (power-on reset) and LVRs (low voltage reset) handle chip power-up or
drops of the supply voltage.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
527
Electrical Characteristics
Figure A-4. MC9S12P-Family - Chip Power-up and Voltage Drops (not scaled)
V
VDDA/VDDX
VLVID
VLVIA
VDD
VLVRD
VLVRA
VPORD
t
LVI
LVI enabled
LVI disabled due to LVR
POR
LVR
S12P-Family Reference Manual, Rev. 1.13
528
Freescale Semiconductor
Electrical Characteristics
A.10
MSCAN
Table A-25. MSCAN Wake-up Pulse Characteristics
Conditions are shown in Table A-4 unless otherwise noted
Num C
Rating
Symbol
Min
Typ
Max
Unit
1
P MSCAN wakeup dominant pulse filtered
tWUP
—
—
1.5
µs
2
P MSCAN wakeup dominant pulse pass
tWUP
5
—
—
µs
A.11
SPI Timing
This section provides electrical parametrics and ratings for the SPI. In Table A-26 the measurement
conditions are listed.
Table A-26. Measurement Conditions
Description
Drive mode
Load capacitance
CLOAD(1), on
all outputs
Thresholds for delay measurement points
1. Timing specified for equal load on all SPI output pins. Avoid asymmetric load.
A.11.1
Value
Unit
Full drive mode
—
50
pF
(20% / 80%) VDDX
V
Master Mode
In Figure A-5 the timing diagram for master mode with transmission format CPHA = 0 is depicted.
SS
(Output)
2
1
SCK
(CPOL = 0)
(Output)
12
13
3
4
5
6
Bit MSB-1. . . 1
MSB IN2
10
MOSI
(Output)
13
4
SCK
(CPOL = 1)
(Output)
MISO
(Input)
12
LSB IN
9
MSB OUT2
Bit MSB-1. . . 1
11
LSB OUT
1. If configured as an output.
2. LSBF = 0. For LSBF = 1, bit order is LSB, bit 1, bit 2... MSB.
Figure A-5. SPI Master Timing (CPHA = 0)
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
529
Electrical Characteristics
In Figure A-6 the timing diagram for master mode with transmission format CPHA=1 is depicted.
SS
(Output)
1
2
12
13
12
13
3
SCK
(CPOL = 0)
(Output)
4
4
SCK
(CPOL = 1)
(Output)
5
MISO
(Input)
6
MSB IN2
Port Data
LSB IN
11
9
MOSI
(Output)
Bit MSB-1. . . 1
Master MSB OUT2
Bit MSB-1. . . 1
Master LSB OUT
Port Data
1.If configured as output
2. LSBF = 0. For LSBF = 1, bit order is LSB, bit 1,bit 2... MSB.
Figure A-6. SPI Master Timing (CPHA = 1)
S12P-Family Reference Manual, Rev. 1.13
530
Freescale Semiconductor
Electrical Characteristics
In Table A-27 the timing characteristics for master mode are listed.
Table A-27. SPI Master Mode Timing Characteristics
Num
C
Characteristic
Symbol
Min
Typ
Max
Unit
1
D
SCK frequency
fsck
1/2048
—
1/2
fbus
1
D
SCK period
tsck
2
D
Enable lead time
tlead
2
—
2048
tbus
—
1/2
—
tsck
3
D
Enable lag time
4
D
Clock (SCK) high or low time
tlag
—
1/2
—
tsck
twsck
—
1/2
—
tsck
5
D
Data setup time (inputs)
tsu
8
—
—
ns
6
D
Data hold time (inputs)
thi
8
—
—
ns
9
D
Data valid after SCK edge
tvsck
—
—
29
ns
10
D
Data valid after SS fall (CPHA = 0)
tvss
—
—
15
ns
11
D
Data hold time (outputs)
tho
20
—
—
ns
12
D
Rise and fall time inputs
trfi
—
—
8
ns
13
D
Rise and fall time outputs
trfo
—
—
8
ns
A.11.2
Slave Mode
In Figure A-7 the timing diagram for slave mode with transmission format CPHA = 0 is depicted.
SS
(Input)
1
12
13 3
12
13
SCK
(CPOL = 0)
(Input)
4
2
4
SCK
(CPOL = 1)
(Input) 10
8
7
MISO
(Output)
9
See
Note
Slave MSB
5
MOSI
(Input)
Bit MSB-1 . . . 1
11
11
Slave LSB OUT
See
Note
6
MSB IN
Bit MSB-1. . . 1
LSB IN
NOTE: Not defined
Figure A-7. SPI Slave Timing (CPHA = 0)
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
531
Electrical Characteristics
In Figure A-8 the timing diagram for slave mode with transmission format CPHA = 1 is depicted.
SS
(Input)
3
1
2
12
13
12
13
SCK
(CPOL = 0)
(Input)
4
4
SCK
(CPOL = 1)
(Input)
See
Note
7
Slave
MSB OUT
5
MOSI
(Input)
8
11
9
MISO
(Output)
Bit MSB-1 . . . 1
Slave LSB OUT
6
MSB IN
Bit MSB-1 . . . 1
LSB IN
NOTE: Not defined
Figure A-8. SPI Slave Timing (CPHA = 1)
In Table A-28 the timing characteristics for slave mode are listed.
Table A-28. SPI Slave Mode Timing Characteristics
Num
C
1
D
1
Symbol
Min
Typ
Max
Unit
SCK frequency
fsck
DC
—
1/4
fbus
D
SCK period
tsck
4
—
∞
tbus
2
D
Enable lead time
tlead
4
—
—
tbus
3
D
Enable lag time
tlag
4
—
—
tbus
4
D
Clock (SCK) high or low time
twsck
4
—
—
tbus
5
D
Data setup time (inputs)
tsu
8
—
—
ns
6
D
Data hold time (inputs)
thi
8
—
—
ns
7
D
Slave access time (time to data active)
ta
—
—
20
ns
8
D
Slave MISO disable time
tdis
—
—
22
9
D
Characteristic
Data valid after SCK edge
tvsck
—
—
29 + 0.5 ⋅
ns
tbus(1)
ns
tbus1
ns
29 + 0.5 ⋅
10
D
Data valid after SS fall
tvss
—
—
11
D
Data hold time (outputs)
tho
20
—
—
ns
12
D
Rise and fall time inputs
trfi
—
—
8
ns
trfo
—
—
8
ns
13
D
Rise and fall time outputs
1. 0.5 tbus added due to internal synchronization delay
S12P-Family Reference Manual, Rev. 1.13
532
Freescale Semiconductor
Ordering Information
Appendix B
Ordering Information
The following figure provides an ordering partnumber example for the devices covered by this data book.
There are two options when ordering a device. Customers must choose between ordering either the maskspecific partnumber or the generic / mask-independent partnumber. Ordering the mask-specific
partnumber enables the customer to specify which particular maskset they will receive whereas ordering
the generic maskset means that FSL will ship the currently preferred maskset (which may change over
time).
In either case, the marking on the device will always show the generic / mask-independent partnumber and
the mask set number.
NOTE
The mask identifier suffix and the Tape & Reel suffix are always both omitted from the
partnumber which is actually marked on the device.
For specific partnumbers to order, please contact your local sales office. The below figure illustrates the
structure of a typical mask-specific ordering number for the MC9S12P-Family devices
S 9 S12 P128
J0 M FT R
Tape & Reel:
R = Tape & Reel
No R = No Tape & Reel
Package Option:
FT = 48 QFN
LH = 64 LQFP
QK = 80 QFP
Temperature Option:
C = -40˚C to 85˚C
V = -40˚C to 105˚C
M = -40˚C to 125˚C
Maskset identifier Suffix:
First digit usually references wafer fab
Second digit usually differentiates mask rev
(This suffix is omitted in generic partnumbers)
Device Title
Controller Family
Main Memory Type:
9 = Flash
3 = ROM (if available)
Status / Partnumber type:
S or SC = Maskset specific partnumber
MC = Generic / mask-independent partnumber
P or PC = prototype status (pre qualification)
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
533
Ordering Information
S12P-Family Reference Manual, Rev. 1.13
534
Freescale Semiconductor
Package Information
Appendix C
Package Information
This section provides the physical dimensions of the MC9S12P-Family packages.
NOTE
The exposed pad of the 48 QFN package should be attached to Vss ground
plane.
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
535
Package Information
C.1
80 QFP Package Mechanical Outline
S12P-Family Reference Manual, Rev. 1.13
536
Freescale Semiconductor
Package Information
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
537
Package Information
S12P-Family Reference Manual, Rev. 1.13
538
Freescale Semiconductor
Package Information
C.2
48 QFN Package Mechanical Outline
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
539
Package Information
S12P-Family Reference Manual, Rev. 1.13
540
Freescale Semiconductor
Package Information
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
541
Package Information
C.3
64 LQFP Package Mechanical Outline
S12P-Family Reference Manual, Rev. 1.13
542
Freescale Semiconductor
Package Information
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
543
Package Information
S12P-Family Reference Manual, Rev. 1.13
544
Freescale Semiconductor
Detailed Register Address Map
Appendix D
Detailed Register Address Map
D.1
Detailed Register Map
The following tables show the detailed register map of the MC9S12P-Family.
0x0000-0x0009 Port Integration Module (PIM) Map 1 of 4
Address
Name
0x0000
PORTA
0x0001
PORTB
0x0002
DDRA
0x0003
DDRB
0x0004
Reserved
0x0005
Reserved
0x0006
Reserved
0x0007
Reserved
0x0008
PORTE
0x0009
DDRE
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PA7
PA6
PA5
PA4
PA3
PA2
PA1
PA0
PB7
PB6
PB5
PB4
PB3
PB2
PB1
PB0
DDRA7
DDRA6
DDRA5
DDRA4
DDRA3
DDRA2
DDRA1
DDRA0
DDRB7
DDRB6
DDRB5
DDRB4
DDRB3
DDRB2
DDRB1
DDRB0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
PE7
PE6
PE5
PE4
PE3
PE2
PE1
PE0
DDRE7
DDRE6
DDRE5
DDRE4
DDRE3
DDRE2
0
0
0x000A-0x000B Module Mapping Conrol (MMC) Map 1 of 2
Address
Name
0x000A
Reserved
0x000B
MODE
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
MODC
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
545
Detailed Register Address Map
0x000C-0x000D Port Integration Module (PIM) Map 2 of 4
Address
Name
0x000C
PUCR
0x000D
RDRIV
Bit 7
R
W
R
W
0
0
Bit 6
BKPUE
Bit 5
0
Bit 4
Bit 3
Bit 2
0
0
0
0
PUPEE
Bit 1
Bit 0
PUPBE
PUPAE
RDPB
RDPA
0
0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
RDPE
0x000E-0x000F Reserved
Address
Name
0x000E
Reserved
0x000F
Reserved
R
W
R
W
0x0010-0x0017 Module Mapping Control (MMC) Map 2 of 2
Address
Name
0x0010
Reserved
0x0011
DIRECT
0x0012
Reserved
0x0013
Reserved
0x0014
Reserved
0x0015
PPAGE
0x0016
Reserved
0x0017
Reserved
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
DP15
DP14
DP13
DP12
DP11
DP10
DP9
DP8
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
PIX7
PIX6
PIX5
PIX4
PIX3
PIX2
PIX1
PIX0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0x0018-0x0019 Reserved
Address
Name
0x0018
Reserved
0x0019
Reserved
R
W
R
W
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546
Freescale Semiconductor
Detailed Register Address Map
0x001A-0x001B Part ID Registers
Address
Name
0x001A
PARTIDH
0x001B
PARTIDL
Bit 7
Bit 6
Bit 5
Bit 4
R
W
R
W
Bit 3
Bit 2
Bit 1
Bit 0
PARTIDH
PARTIDL
0x001C-0x001F Port Intergartion Module (PIM) Map 3 of 4
Address
Name
0x001C
ECLKCTL
0x001D
Reserved
0x001E
IRQCR
0x001F
Reserved
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
NECLK
NCLKX2
DIV16
EDIV4
EDIV3
EDIV2
EDIV1
EDIV0
0
0
0
0
0
0
0
0
IRQE
IRQEN
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
BDM
DBGBRK
0
0
0
0
0
0x0020-0x002F Debug Module (S12SDBG) Map
Address
Name
0x0020
DBGC1
0x0021
DBGSR
0x0022
DBGTCR
0x0023
DBGC2
0x0024
DBGTBH
0x0025
DBGTBL
0x0026
DBGCNT
0x0027
DBGSCRX
0x0027
DBGMFR
0x0028
(1)
0x0028
(2)
DBGACTL
DBGBCTL
Bit 7
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
ARM
TBF
0
Bit 6
Bit 5
0
TRIG
0
0
TSOURCE
0
SSF2
COMRV
SSF1
0
TRCMOD
SSF0
TALIGN
0
0
0
0
0
0
Bit 15
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
TBF
0
0
0
0
0
SC3
SC2
SC1
SC0
0
0
0
0
0
MC2
MC1
MC0
SZE
SZ
TAG
BRK
RW
RWE
SZE
SZ
TAG
BRK
RW
RWE
ABCM
CNT
0
0
COMPE
COMPE
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
547
Detailed Register Address Map
0x0020-0x002F Debug Module (S12SDBG) Map
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
R
0
0
0x0028
DBGCCTL
TAG
BRK
RW
RWE
(3)
W
R
0
0
0
0
0
0
0x0029
DBGXAH
W
R
0x002A
DBGXAM
Bit 15
14
13
12
11
10
W
R
0x002B
DBGXAL
Bit 7
6
5
4
3
2
W
R
0x002C
DBGADH
Bit 15
14
13
12
11
10
W
R
0x002D
DBGADL
Bit 7
6
5
4
3
2
W
R
0x002E
DBGADHM
Bit 15
14
13
12
11
10
W
R
0x002F
DBGADLM
Bit 7
6
5
4
3
2
W
1. This represents the contents if the Comparator A or C control register is blended into this address
2. This represents the contents if the Comparator B or D control register is blended into this address
3. This represents the contents if the Comparator B or D control register is blended into this address
0
Bit 0
COMPE
17
Bit 16
9
Bit 8
1
Bit 0
9
Bit 8
1
Bit 0
9
Bit 8
1
Bit 0
0x0030-0x0033 Reserved
Address
Name
0x0030
Reserved
0x0031
Reserved
0x0032
Reserved
0x0033
Reserved
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit 2
Bit 1
Bit 0
0x0034-0x003F Clock Reset and Power Management (CPMU) Map
Address
Name
R
W
R
0x0035 CPMUREFDIV
W
CPMUPOSTDI R
0x0036
V
W
R
0x0037
CPMUFLG
W
0x0034
CPMUSYNR
Bit 7
Bit 6
Bit 5
Bit 4
VCOFRQ[1:0]
REFFRQ[1:0]
Bit 3
SYNDIV[5:0]
0
0
0
0
RTIF
PORF
LVRF
0
REFDIV[3:0]
POSTDIV[4:0]
LOCKIF
LOCK
ILAF
OSCIF
UPOSC
S12P-Family Reference Manual, Rev. 1.13
548
Freescale Semiconductor
Detailed Register Address Map
0x0034-0x003F Clock Reset and Power Management (CPMU) Map
Address
Name
0x0038
CPMUINT
0x0039
CPMUCLKS
0x003A
CPMUPLL
0x003B
CPMURTI
0x003C
CPMUCOP
0x003D
Reserved
0x003E
Reserved
0x003F
CPMU
ARMCOP
Bit 7
R
RTIE
W
R
PLLSEL
W
R
0
W
R
W
R
W
R
W
R
W
R
W
Bit 6
Bit 5
0
0
PSTP
0
Bit 4
LOCKIE
Bit 3
Bit 2
0
0
PRE
PCE
RTIOSCS
EL
COPOSC
SEL
0
0
0
0
RTR2
RTR1
RTR0
CR2
CR1
CR0
0
0
0
0
0
0
0
2
0
1
0
Bit 0
0
0
FM1
FM0
RTR5
RTR4
RTR3
0
0
RTDEC
RTR6
WCOP
RSBCK
0
0
0
WRTMAS
K
0
0
0
0
0
Bit 7
0
6
0
5
0
0
Reserved For Factory Test
0
Reserved For Factory Test
0
0
4
3
Bit 1
OSCIE
Bit 0
0
0x0040-0x006F Timer Module (TIM) Map
Address
Name
0x0040
TIOS
0x0041
CFORC
0x0042
OC7M
0x0043
OC7D
0x0044
TCNTH
0x0045
TCNTL
0x0046
TSCR1
0x0047
TTOV
0x0048
TCTL1
0x0049
TCTL2
0x004A
TCTL3
0x004B
TCTL4
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
IOS7
IOS6
IOS5
IOS4
IOS3
IOS2
IOS1
IOS0
0
FOC7
0
FOC6
0
FOC5
0
FOC4
0
FOC3
0
FOC2
0
FOC1
0
FOC0
OC7M7
OC7M6
OC7M5
OC7M4
OC7M3
OC7M2
OC7M1
OC7M0
OC7D7
OC7D6
OC7D5
OC7D4
OC7D3
OC7D2
OC7D1
OC7D0
Bit 15
14
13
12
11
10
9
Bit 8
Bit 7
6
5
4
3
2
1
Bit 0
TEN
TSWAI
TSFRZ
TFFCA
PRNT
0
0
0
TOV7
TOV6
TOV5
TOV4
TOV3
TOV2
TOV1
TOV0
OM7
OL7
OM6
OL6
OM5
OL5
OM4
OL4
OM3
OL3
OM2
OL2
OM1
OL1
OM0
OL0
EDG7B
EDG7A
EDG6B
EDG6A
EDG5B
EDG5A
EDG4B
EDG4A
EDG3B
EDG3A
EDG2B
EDG2A
EDG1B
EDG1A
EDG0B
EDG0A
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
549
Detailed Register Address Map
0x0040-0x006F Timer Module (TIM) Map
Address
Name
0x004C
TIE
0x004D
TSCR2
0x004E
TFLG1
0x004F
TFLG2
0x0050
TC0H
0x0051
TC0L
0x0052
TC1H
0x0053
TC1L
0x0054
TC2H
0x0055
TC2L
0x0056
TC3H
0x0057
TC3L
0x0058
TC4H
0x0059
TC4L
0x005A
TC5H
0x005B
TC5L
0x005C
TC6H
0x005D
TC6L
0x005E
TC7H
0x005F
TC7L
0x0060
PACTL
0x0061
PAFLG
0x0062
PACNTH
Bit 7
R
C7I
W
R
TOI
W
R
C7F
W
R
TOF
W
R
Bit 15
W
R
Bit 7
W
R
Bit 15
W
R
Bit 7
W
R
Bit 15
W
R
Bit 7
W
R
Bit 15
W
R
Bit 7
W
R
Bit 15
W
R
Bit 7
W
R
Bit 15
W
R
Bit 7
W
R
Bit 15
W
R
Bit 7
W
R
Bit 15
W
R
Bit 7
W
R
0
W
R
0
W
R
PACNT15
W
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
C6I
C5I
C4I
C3I
C2I
C1I
C0I
0
0
0
TCRE
PR2
PR1
PR0
C6F
C5F
C4F
C3F
C2F
C1F
C0F
0
0
0
0
0
0
0
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 14
Bit 13
Bit 12
Bit 11
Bit 10
Bit 9
Bit 8
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PAEN
PAMOD
PEDGE
CLK1
CLK0
PAOVI
PAI
0
0
0
0
0
PAOVF
PAIF
PACNT14
PACNT13
PACNT12
PACNT11
PACNT10
PACNT9
PACNT8
S12P-Family Reference Manual, Rev. 1.13
550
Freescale Semiconductor
Detailed Register Address Map
0x0040-0x006F Timer Module (TIM) Map
Address
Name
0x0063
PACNTL
0x0064–
0x006B
Reserved
0x006C
OCPD
0x006D
Reserved
0x006E
PTPSR
0x006F
Reserved
Bit 7
R
PACNT7
W
R
0
W
R
OCPD7
W
R
W
R
PTPS7
W
R
0
W
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PACNT6
PACNT5
PACNT4
PACNT3
PACNT2
PACNT1
PACNT0
0
0
0
0
0
0
0
OCPD6
OCPD5
OCPD4
OCPD3
OCPD2
OCPD1
OCPD0
PTPS6
PTPS5
PTPS4
PTPS3
PTPS2
PTPS1
PTPS0
0
0
0
0
0
0
0
0x0070-0x009F Analog to Digital Converter 12-Bit 10-Channel (ATD) Map
Address
Name
0x0070
ATDCTL0
0x0071
ATDCTL1
0x0072
ATDCTL2
0x0073
ATDCTL3
0x0074
ATDCTL4
0x0075
ATDCTL5
0x0076
ATDSTAT0
0x0077
Reserved
0x0078
ATDCMPEH
0x0079
ATDCMPEL
0x007A
ATDSTAT2H
0x007B
ATDSTAT2L
0x007C
ATDDIENH
0x007D
ATDDIENL
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
0
0
0
0
ETRIG
SEL
SRES1
SRES0
AFFC
DJM
SMP2
0
0
SCF
Bit 3
Bit 2
Bit 1
Bit 0
WRAP3
WRAP2
WRAP1
WRAP0
SMP_DIS
ETRIG
CH3
ETRIG
CH2
ETRIG
CH1
ETRIG
CH0
ICLKSTP
ETRIGLE
ETRIGP
ETRIGE
ASCIE
ACMPIE
S8C
S4C
S2C
S1C
FIFO
FRZ1
FRZ0
SMP1
SMP0
PRS4
PRS3
PRS2
PRS1
PRS0
SC
SCAN
MULT
CD
CC
CB
CA
ETORF
FIFOR
CC3
CC2
CC1
CC0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
CMPE[9:8]
CMPE[7:0]
CCF[9:8]
CCF[7:0]
0
0
0
0
0
0
IEN[9:8]
IEN[7:0]
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
551
Detailed Register Address Map
0x0070-0x009F Analog to Digital Converter 12-Bit 10-Channel (ATD) Map
Address
0x007E
0x007F
0x0080
0x0081
0x0082
0x0083
0x0084
0x0085
0x0086
0x0087
0x0088
0x0089
0x008A
0x008B
0x008C
0x008D
0x008E
0x008F
0x090
0x091
0x092
0x093
0x094
Name
R
ATDCMPHTH
W
R
ATDCMPHTL
W
R
ATDDR0H
W
R
ATDDR0L
W
R
ATDDR1H
W
R
ATDDR1L
W
R
ATDDR2H
W
R
ATDDR2L
W
R
ATDDR3H
W
R
ATDDR3L
W
R
ATDDR4H
W
R
ATDDR4L
W
R
ATDDR5H
W
R
ATDDR5L
W
R
ATDDR6H
W
R
ATDDR6L
W
R
ATDDR7H
W
R
ATDDR7L
W
R
ATDDR8H
W
R
ATDDR8L
W
R
ATDDR9H
W
R
ATDDR9L
W
R
ATDDR10H
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
0
0
0
0
0
0
Bit 1
Bit 0
CMPHT[9:8]
CMPHT[7:0]
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
S12P-Family Reference Manual, Rev. 1.13
552
Freescale Semiconductor
Detailed Register Address Map
0x0070-0x009F Analog to Digital Converter 12-Bit 10-Channel (ATD) Map
Address
Name
0x095
ATDDR10L
0x096
ATDDR11H
0x097
ATDDR11L
0x098
ATDDR12H
0x099
ATDDR12L
0x09A
ATDDR13H
0x09B
ATDDR13L
0x09C
ATDDR14H
0x09D
ATDDR14L
0x09E
ATDDR15H
0x009F
ATDDR15L
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
Bit15
14
13
12
11
10
9
Bit8
Bit7
Bit6
0
0
0
0
0
0
0x00A0-0x00C7 Pulse Width Modulator 6-Channels (PWM) Map
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0x00A0
PWME
R
W
0
0
PWME5
PWME4
PWME3
PWME2
PWME1
PWME0
0x00A1
PWMPOL
R
W
PPOL5
PPOL4
PPOL3
PPOL2
PPOL1
PPOL0
0x00A2
PWMCLK
R
W
0
PCLK5
PCLK4
PCLK3
PCLK2
PCLK1
PCLK0
0x00A3
PWMPRCLK
0
0x00A4
PWMCAE
R
W
R
W
PCKB1
PCKB0
PCKA2
PCKA1
PCKA0
CAE5
CAE4
CAE3
CAE2
CAE1
CAE0
0x00A5
PWMCTL
R
W
0
CON45
CON23
CON01
PSWAI
PFRZ
0
0
0x00A6
PWMTST
Test Only
0x00A7
PWMPRSC
0x00A8
PWMSCLA
R
W
R
W
R
W
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
PCKB2
0
0
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
553
Detailed Register Address Map
0x00A0-0x00C7 Pulse Width Modulator 6-Channels (PWM) Map
Address
0x00A9
0x00AA
0x00AB
0x00AC
0x00AD
0x00AE
0x00AF
0x00B0
0x00B1
0x00B2
0x00B3
0x00B4
0x00B5
0x00B6
0x00B7
0x00B8
0x00B9
0x00BA
0x00BB
0x00BC
0x00BD
0x00BE
0x00BF0x00C7
Name
R
PWMSCLB
W
R
PWMSCNTA
W
R
PWMSCNTB
W
R
PWMCNT0
W
R
PWMCNT1
W
R
PWMCNT2
W
R
PWMCNT3
W
R
PWMCNT4
W
R
PWMCNT5
W
R
PWMPER0
W
R
PWMPER1
W
R
PWMPER2
W
R
PWMPER3
W
R
PWMPER4
W
R
PWMPER5
W
R
PWMDTY0
W
R
PWMDTY1
W
R
PWMDTY2
W
R
PWMDTY3
W
R
PWMDTY4
W
R
PWMDTY5
W
R
PWMSDN
W
R
Reserved
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit 7
0
Bit 7
0
Bit 7
0
Bit 7
0
Bit 7
0
Bit 7
0
6
0
6
0
6
0
6
0
6
0
6
0
5
0
5
0
5
0
5
0
5
0
5
0
4
0
4
0
4
0
4
0
4
0
4
0
3
0
3
0
3
0
3
0
3
0
3
0
2
0
2
0
2
0
2
0
2
0
2
0
1
0
1
0
1
0
1
0
1
0
1
0
Bit 0
0
Bit 0
0
Bit 0
0
Bit 0
0
Bit 0
0
Bit 0
0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
Bit 7
6
5
4
3
2
1
Bit 0
PWMIF
PWMIE
0
PWM5IN
PWM5INL
PWM5
ENA
0
0
0
0
0
0
0
PWMLVL
PWRSTRT
0
0
S12P-Family Reference Manual, Rev. 1.13
554
Freescale Semiconductor
Detailed Register Address Map
0x00C8-0x00CF Serial Communication Interface (SCI) Map
Address
Name
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
R
0x00C8
SCIBDH(1)
IREN
TNP1
TNP0
SBR12
SBR11
W
R
SBR7
SBR6
SBR5
SBR4
SBR3
0x00C9
SCIBDL1
W
R
LOOPS
SCISWAI
RSRC
M
WAKE
0x00CA
SCICR11
W
R
0
0
0
0
RXEDGIF
0x00C8 SCIASR1(2)
W
R
0
0
0
0
RXEDGIE
0x00C9
SCIACR12
W
R
0
0
0
0
0
0x00CA
SCIACR22
W
R
0x00CB
SCICR2
TIE
TCIE
RIE
ILIE
TE
W
R
TDRE
TC
RDRF
IDLE
OR
0x00CC
SCISR1
W
R
0
0
0x00CD
SCISR2
AMAP
TXPOL
RXPOL
W
R
R8
0
0
0
0x00CE
SCIDRH
T8
W
R
R7
R6
R5
R4
R3
0x00CF
SCIDRL
W
T7
T6
T5
T4
T3
1. Those registers are accessible if the AMAP bit in the SCI0SR2 register is set to zero
2. Those registers are accessible if the AMAP bit in the SCI0SR2 register is set to one
Bit 2
Bit 1
Bit 0
SBR10
SBR9
SBR8
SBR2
SBR1
SBR0
ILT
PE
PT
BERRV
BERRIF
BKDIF
BERRIE
BKDIE
BERRM1
BERRM0
BKDFE
RE
RWU
SBK
NF
FE
PF
BRK13
TXDIR
0
0
0
R2
T2
R1
T1
R0
T0
0
RAF
0x00D0-0x00D7 Reserved
Address
Name
0x00D00x00D7
Reseved
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
0x00D8-0x00DF Serial Peripheral Interface (SPI) Map
Address
Name
0x00D8
SPICR1
0x00D9
SPICR2
0x00DA
SPIBR
0x00DB
SPISR
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
SPIE
SPE
SPTIE
MSTR
CPOL
CPHA
SSOE
LSBFE
MODFEN
BIDIROE
SPISWAI
SPC0
SPR2
SPR1
SPR0
0
0
0
0
0
SPIF
XFRW
0
SPPR2
SPPR1
SPPR0
0
SPTEF
MODF
0
0
0
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
555
Detailed Register Address Map
0x00D8-0x00DF Serial Peripheral Interface (SPI) Map
Address
Name
0x00DC
SPIDRH
0x00DD
SPI0DRL
0x00DE
Reserved
0x00DF
Reserved
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
R15
T15
R7
T7
0
R14
T14
R6
T6
0
R13
T13
R5
T5
0
R12
T12
R4
T4
0
R11
T11
R3
T3
0
R10
T10
R2
T2
0
R9
T9
R1
T1
0
R8
T8
R0
T0
0
0
0
0
0
0
0
0
0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
0x00E0-0x00FF Reserved
Address
Name
0x00E00x00FF
Reserved
R
W
0x0100-0x0113 NVM Contol Register (FTMRC) Map
Address
Name
0x0100
FCLKDIV
0x0101
FSEC
0x0102
FCCOBIX
0x0103
FRSV0
0x0104
FCNFG
0x0105
FERCNFG
0x0106
FSTAT
0x0107
FERSTAT
0x0108
FPROT
0x0109
DFPROT
0x010A
FCCOBHI
0x010B
FCCOBLO
0x010C
FRSV1
Bit 7
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
FDIV6
FDIV5
FDIV4
FDIV3
FDIV2
FDIV1
FDIV0
KEYEN1
KEYEN0
RNV5
RNV4
RNV3
RNV2
SEC1
SEC0
0
0
0
0
0
CCOBIX2
CCOBIX1
CCOBIX0
0
0
0
0
0
0
0
0
0
0
0
0
FDFD
FSFD
0
0
0
0
0
DFDIE
SFDIE
ACCERR
FPVIOL
MGBUSY
RSVD
0
0
0
0
FPHDIS
FPHS1
FPHS0
0
0
0
CCOB15
CCOB14
CCOB13
CCOB7
CCOB6
0
0
FDIVLD
CCIE
0
CCIF
0
FPOPEN
DPOPEN
0
0
RNV6
IGNSF
MGSTAT1 MGSTAT0
DFDIF
SFDIF
FPLDIS
FPLS1
FPLS0
DPS3
DPS2
DPS1
DPS0
CCOB12
CCOB11
CCOB10
CCOB9
CCOB8
CCOB5
CCOB4
CCOB3
CCOB2
CCOB1
CCOB0
0
0
0
0
0
0
S12P-Family Reference Manual, Rev. 1.13
556
Freescale Semiconductor
Detailed Register Address Map
0x0100-0x0113 NVM Contol Register (FTMRC) Map
Address
Name
0x010D
FRSV2
0x010E
FRSC3
0x010F
FRSV4
0x0110
FOPT
0x0111
FRSV5
0x0112
FRSV6
0x0113
FRSV7
R
W
R
W
R
W
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
NV7
NV6
NV5
NV4
NV3
NV2
NV1
NV0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0x0114-0x011F Reserved
Address
Name
0x01140x011F
Reserved
R
W
0x0120 Interrupt Vector Base Register
Address
0x0120
Name
IVBR
Bit 7
Bit 6
R
W
IVB_ADDR[7:0]
0x0121-0x013F Reserved
Address
Name
0x01140x011F
Reserved
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
TIME
WUPE
SLPRQ
INITRQ
SLPAK
INITAK
BRP1
BRP0
0x0140-0x017F MSCAN Map
Address
Name
0x0140
CAN0CTL0
0x0141
CAN0CTL1
0x0142
CAN0BTR0
Bit 7
R
RXFRM
W
R
CANE
W
R
SJW1
W
RXACT
CSWAI
SYNCH
CLKSRC
LOOPB
LISTEN
BORM
WUPM
SJW0
BRP5
BRP4
BRP3
BRP2
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
557
Detailed Register Address Map
0x0140-0x017F MSCAN Map
Address
Name
0x0143
CAN0BTR1
0x0144
CAN0RFLG
0x0145
CAN0RIER
0x0146
CAN0TFLG
0x0147
CAN0TIER
0x0148
CAN0TARQ
0x0149
CAN0TAAK
0x014A
CAN0TBSEL
0x014B
CAN0IDAC
0x014C
Reserved
0x014D
CAN0MISC
0x014E
CAN0RXERR
0x014F
CAN0TXERR
0x01500x0153
CAN0IDAR0CAN0IDAR3
0x0154- CAN0IDMR00x0157 CAN0IDMR3
0x01580x015B
CAN0IDAR4CAN0IDAR7
0x015C- CAN0IDMR40x015F CAN0IDMR7
0x01600x016F
CAN0RXFG
0x01700x017F
CAN0TXFG
Bit 7
R
SAMP
W
R
WUPIF
W
R
WUPIE
W
R
0
W
R
0
W
R
0
W
R
0
W
R
0
W
R
0
W
R
0
W
R
0
W
R RXERR7
W
R TXERR7
W
R
AC7
W
R
AM7
W
R
AC7
W
R
AM7
W
R
W
R
W
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
TSEG22
TSEG21
TSEG20
TSEG13
TSEG12
TSEG11
TSEG10
RSTAT1
RSTAT0
TSTAT1
TSTAT0
OVRIF
RXF
CSCIE
RSTATE1
RSTATE0
TSTATE1
TSTATE0
OVRIE
RXFIE
0
0
0
0
TXE2
TXE1
TXE0
0
0
0
0
TXEIE2
TXEIE1
TXEIE0
0
0
0
0
ABTRQ2
ABTRQ1
ABTRQ0
0
0
0
0
ABTAK2
ABTAK1
ABTAK0
0
0
0
0
TX2
TX1
TX0
IDAM1
IDAM0
0
IDHIT2
IDHIT1
IDHIT0
0
0
0
0
0
0
0
0
0
0
0
0
0
RXERR6
RXERR5
RXERR4
RXERR3
RXERR2
RXERR1
RXERR0
TXERR6
TXERR5
TXERR4
TXERR3
TXERR2
TXERR1
TXERR0
AC6
AC5
AC4
AC3
AC2
AC1
AC0
AM6
AM5
AM4
AM3
AM2
AM1
AM0
AC6
AC5
AC4
AC3
AC2
AC1
AC0
AM6
AM5
AM4
AM3
AM2
AM1
AM0
CSCIF
0
BOHOLD
FOREGROUND RECEIVE BUFFER
(SeeTable )
FOREGROUND TRANSMIT BUFFER
(SeeTable )
S12P-Family Reference Manual, Rev. 1.13
558
Freescale Semiconductor
Detailed Register Address Map
MSCAN Foreground Receive and Transmit Buffer Layout
Address
0xXXX0
0xXXX1
0xXXX2
0xXXX3
Name
Extended ID
Standard ID
CANxRIDR0
Extended ID
Standard ID
CANxRIDR1
Extended ID
Standard ID
CANxRIDR2
Extended ID
Standard ID
CANxRIDR3
0xXXX4- CANxRDSR00xXXXB CANxRDSR7
0xXXXC
CANRxDLR
0xXXXD
Reserved
0xXXXE CANxRTSRH
0xXXXF
0xXX10
0xXX0x
XX10
0xXX12
0xXX13
CANxRTSRL
Extended ID
CANxTIDR0
Standard ID
Extended ID
CANxTIDR1
Standard ID
Extended ID
CANxTIDR2
Standard ID
Extended ID
CANxTIDR3
Standard ID
0xXX14- CANxTDSR0–
0xXX1B CANxTDSR7
0xXX1C
CANxTDLR
0xXX1D
CANxTTBPR
R
R
W
R
R
W
R
R
W
R
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
ID28
ID10
ID27
ID9
ID26
ID8
ID25
ID7
ID24
ID6
ID23
ID5
ID22
ID4
ID21
ID3
ID20
ID2
ID19
ID1
ID18
ID0
SRR=1
RTR
IDE=1
IDE=0
ID17
ID16
ID15
ID14
ID13
ID12
ID11
ID10
ID9
ID8
ID7
ID6
ID5
ID4
ID3
ID2
ID1
ID0
RTR
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DLC3
DLC2
DLC1
DLC0
TSR15
TSR14
TSR13
TSR12
TSR11
TSR10
TSR9
TSR8
TSR7
TSR6
TSR5
TSR4
TSR3
TSR2
TSR1
TSR0
ID28
ID27
ID26
ID25
ID24
ID23
ID22
ID21
ID10
ID9
ID8
ID7
ID6
ID5
ID4
ID3
ID20
ID19
ID18
SRR=1
IDE=1
ID17
ID16
ID15
ID2
ID1
ID0
RTR
IDE=0
ID14
ID13
ID12
ID11
ID10
ID9
ID8
ID7
ID6
ID5
ID4
ID3
ID2
ID1
ID0
RTR
DB7
DB6
DB5
DB4
DB3
DB2
DB1
DB0
DLC3
DLC2
DLC1
DLC0
PRIO3
PRIO2
PRIO1
PRIO0
PRIO7
PRIO6
PRIO5
PRIO4
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
559
Detailed Register Address Map
MSCAN Foreground Receive and Transmit Buffer Layout
Address
0xXX1E
0xXX1F
Name
R
CANxTTSRH
W
R
CANxTTSRL
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
TSR15
TSR14
TSR13
TSR12
TSR11
TSR10
TSR9
TSR8
TSR7
TSR6
TSR5
TSR4
TSR3
TSR2
TSR1
TSR0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
0x0180-023F Reserved
Address
Name
0x01800x023F
Reserved
R
W
0x0240 -0x027F Port Integration Module (PIM) Map 4 of 4
Address
Name
0x0240
PTT
0x0241
PTIT
0x0242
DDRT
0x0243
RDRT
0x0244
PERT
0x0245
PPST
0x0246
Reserved
0x0247
PTTRR
Bit 7
R
PTT7
W
R
PTIT7
W
R
DDRT7
W
R
RDRT7
W
R
PERT7
W
R
PPST7
W
R
0
W
R
PTTRR7
W
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PTT6
PTT5
PTT4
PTT3
PTT2
PTT1
PTT0
PTIT6
PTIT5
PTIT4
PTIT3
PTIT2
PTIT1
PTIT0
DDRT6
DDRT5
DDRT4
DDRT3
DDRT2
DDRT1
DDRT0
RDRT6
RDRT5
RDRT4
RDRT3
RDRT2
RDRT1
RDRT0
PERT6
PERT5
PERT4
PERT3
PERT2
PERT1
PERT0
PPST6
PPST5
PPST4
PPST3
PPST2
PPST1
PPST0
0
0
0
0
0
0
0
PTTRR6
PTTRR5
PTTRR4
PTTRR2
PTTRR1
PTTRR0
0
S12P-Family Reference Manual, Rev. 1.13
560
Freescale Semiconductor
Detailed Register Address Map
0x0240 -0x027F Port Integration Module (PIM) Map 4 of 4
Address
Name
0x0248
PTS
0x0249
PTIS
0x024A
DDRS
0x024B
RDRS
0x024C
PERS
0x024D
PPSS
0x024E
WOMS
0x024F
Reserved
0x0250
PTM
0x0251
PTIM
0x0252
DDRM
0x0253
RDRM
0x0254
PERM
0x0255
PPSM
0x0256
WOMM
0x0257
MODRR
0x0258
PTP
0x0259
PTIP
0x025A
DDRP
0x025B
RDRP
0x025C
PERP
0x025D
PPSP
0x025E
PIEP
0x025F
PIFP
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
PTS7
PTS6
PTS5
PTS4
PTS3
PTS2
PTS1
PTS0
PTIS7
PTIS6
PTIS5
PTIS4
PTIS3
PTIS2
PTIS1
PTIS0
DDRS7
DDRS6
DDRS5
DDRS4
DDRS3
DDRS2
DDRS1
DDRS0
RDRS7
RDRS6
RDRS5
RDRS4
RDRS3
RDRS2
RDRS1
RDRS0
PERS7
PERS6
PERS5
PERS4
PERS3
PERS2
PERS1
PERS0
PPSS7
PPSS6
PPSS5
PPSS4
PPSS3
PPSS2
PPSS1
PPSS0
WOMS7
WOMS6
WOMS5
WOMS4
WOMS3
WOMS2
WOMS1
WOMS0
0
0
0
0
0
0
0
0
PTM7
PTM6
PTM5
PTM4
PTM3
PTM2
PTM1
PTM0
PTIM7
PTIM6
PTIM5
PTIM4
PTIM3
PTIM2
PTIM1
PTIM0
DDRM7
DDRM6
DDRM5
DDRM4
DDRM3
DDRM2
DDRM1
DDRM0
RDRM7
RDRM6
RDRM5
RDRM4
RDRM3
RDRM2
RDRM1
RDRM0
PERM7
PERM6
PERM5
PERM4
PERM3
PERM2
PERM1
PERM0
PPSM7
PPSM6
PPSM5
PPSM4
PPSM3
PPSM2
PPSM1
PPSM0
WOMM7
WOMM6
WOMM5
WOMM4
WOMM3
WOMM2
WOMM1
WOMM0
MODRR7
MODRR6
0
0
0
0
PTP7
PTP6
PTP5
PTP4
PTP3
PTP2
PTP1
PTP0
PTIP7
PTIP6
PTIP5
PTIP4
PTIP3
PTIP2
PTIP1
PTIP0
DDRP7
DDRP6
DDRP5
DDRP4
DDRP3
DDRP2
DDRP1
DDRP0
RDRP7
RDRP6
RDRP5
RDRP4
RDRP3
RDRP2
RDRP1
RDRP0
PERP7
PERP6
PERP5
PERP4
PERP3
PERP2
PERP1
PERP0
PPSP7
PPSP6
PPSP5
PPSP4
PPSP3
PPSP2
PPSP1
PPSS0
PIEP7
PIEP6
PIEP5
PIEP4
PIEP3
PIEP2
PIEP1
PIEP0
PIFP7
PIFP6
PIFP5
PIFP4
PIFP3
PIFP2
PIFP1
PIFP0
0
MODRR4
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
561
Detailed Register Address Map
0x0240 -0x027F Port Integration Module (PIM) Map 4 of 4
Address
Name
0x0260
Reserved
0x0261
Reserved
0x0262
Reserved
0x0263
Reserved
0x0264
Reserved
0x0265
Reserved
0x0266
Reserved
0x0267
Reserved
0x0268
PTJ
0x0269
PTIJ
0x026A
DDRJ
0x026B
RDRJ
0x026C
PERJ
0x026D
PPSJ
0x026E
PIEJ
0x026f
PIFJ
0x0270
PT0AD0
0x0271
PT1AD0
0x0272
DDR0AD0
0x0273
DDR1AD0
0x0274
RDR0AD0
0x0275
RDR1AD0
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
R
W
0
0
0
0
0
0
0
0
R
W
R
W
R
W
R
W
0
00
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
R
W
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
PTJ7
PTJ6
0
0
0
PTJ2
PTJ1
PTJ0
PTIJ7
PTIJ6
0
0
0
PTIJ12
PTIJ1
PTIJ0
DDRJ7
DDRJ6
0
0
0
DDRJ2
DDRJ1
DDRJ0
RDRJ7
RDRJ6
0
0
0
RDRJ2
RDRJ1
RDRJ0
PERJ7
PERJ6
0
0
0
PERJ2
PERJ1
PERJ0
PPSJ7
PPSJ6
0
0
0
PPSJ2
PPSJ1
PPSJ0
PIEJ7
PIEJ6
0
0
0
PIEJ2
PIEJ1
PIEJ0
PIFJ7
PIFJ6
0
0
0
PIFJ2
PIFJ1
PIFJ0
PT0AD0
7
PT1AD0
7
PT0AD0
6
PT1AD0
6
PT0AD0
5
PT1AD0
5
PT0AD0
4
PT1AD0
4
PT0AD0
3
PT1AD0
3
PT0AD0
2
PT1AD0
2
PT0AD0
1
PT1AD0
1
PT0AD0
0
PT1AD0
0
DDR0AD0 DDR0AD0 DDR0AD0 DDR0AD0 DDR0AD0 DDR0AD0 DDR0AD0 DDR0AD0
7
6
5
4
3
2
1
0
DDR1AD0 DDR1AD0 DDR1AD0 DDR1AD0 DDR1AD0 DDR1AD0 DDR1AD0 DDR1AD0
7
6
5
4
3
2
1
0
RDR0AD0 RDR0AD0 RDR0AD0 RDR0AD0 RDR0AD0 RDR0AD0 RDR0AD0 RDR0AD0
7
6
5
4
3
2
1
0
RDR1AD0 RDR1AD0 RDR1AD0 RDR1AD0 RDR1AD0 RDR1AD0 RDR1AD0 RDR1AD0
7
6
5
4
3
2
1
0
S12P-Family Reference Manual, Rev. 1.13
562
Freescale Semiconductor
Detailed Register Address Map
0x0240 -0x027F Port Integration Module (PIM) Map 4 of 4
Address
Name
0x0276
PER0AD0
0x0277
PER1AD0
0x02780x027F
Reserved
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
R PER0AD0 PER0AD0 PER0AD0 PER0AD0 PER0AD0 PER0AD0 PER0AD0 PER0AD0
7
6
5
4
3
2
1
0
W
R PER1AD0 PER1AD0 PER1AD0 PER1AD0 PER1AD0 PER1AD0 PER1AD0 PER1AD0
7
6
5
4
3
2
1
0
W
R
0
0
0
0
0
0
0
0
W
0x0280-0x02EF Reserved
Address
0x02800x02EF
Name
Reserved
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
Bit 1
Bit 0
HTIE
HTIF
LVIE
LVIF
APIE
APIF
0
0
0x02F0-0x02FF Clock and Power Management Unit (CPMU) Map 2 of 2
Address
Name
0x02F0
CPMUHTCL
0x02F1
CPMULVCTL
0x02F2 CPMUAPICTL
0x02F3
VREGAPITR
0x02F4
CPMUAPIRH
0x02F5
CPMUAPIRL
0x02F6
Reserved
0x02F7
CPMUHTTR
0x02F8
CPMU
IRCTRIMH
0x02F9
CPMU
IRCTRIML
0x02FA
CPMUOSC
0x02FB
CPMUPROT
0x02FC
Reserved
Bit 7
R
0
W
R
0
W
R
APICLK
W
R
APITR5
W
R
APIR15
W
R
APIR7
W
R
0
W
R
HTOEN
W
R
W
R
W
R
OSCE
W
R
0
W
R
0
W
Bit 6
0
Bit 5
VSEL
0
0
0
0
APITR4
Bit 4
0
Bit 3
HTEN
Bit 2
HTDS
0
0
LVDS
APIFES
APIEA
APIFE
APITR3
APITR2
APITR1
APITR0
APIR14
APIR13
APIR12
APIR11
APIR10
APIR9
APIR8
APIR6
APIR5
APIR4
APIR3
APIR2
APIR1
APIR0
0
0
0
0
0
0
0
0
0
0
HTTR3
HTTR2
HTTR1
HTTR0
0
0
TCTRIM[3:0]
IRCTRIM[9:8]
IRCTRIM[7:0]
OSCBW
0
OSCFILT[4:0]
0
0
0
0
0
0
0
0
0
0
0
0
PROT
0
S12P-Family Reference Manual, Rev. 1.13
Freescale Semiconductor
563
Detailed Register Address Map
0x0300-0x03FF Reserved
Address
0x03000x03FF
Name
Reserved
R
W
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
0
0
0
0
0
S12P-Family Reference Manual, Rev. 1.13
564
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